t70
ììIIIìEIìIìNCES
I{ o f ¡n ân n, \\¡. : Ill[onoloníeeigenscltTflctt cles Steffensen-lterfaln.cns, Acquationes Math., 12, 27-3r (7s75).
'I o lrn s on' L' w' nnd S ch o ì 2, I). rì. : on steffensett's DteIr,otr,sIANI J. Nunr. Anaì.,
5,296-302 (1968).
Kantorovich,L.\'.allr.r Aì<iìov,G.p.:Ã-uncrionnlnrrarysis,2ndcd.,Ne¡,yorr<,.
Pergamon Prcss (1982).
stef f enscrì' J. F.: ri¿mar*s ott ileration, Skancr. Aktuar. Tidsriv., r8,64- 72(1g33)..
u I 'nr , S. Y. : -Ecr¿nsioil:f flllfercil.s mcrhod for soluitt¡¡ ttonlineaLí ip'eratot. equalÌons,.
USSR Conrp. ì\Iath., 4, 159-165 (1964).
I'UNCTIONÁ.I_,, NORMAI_, WR,ITING OPERATORS
ZELIIIER AI.EXANDRU (Ctuj_Napoca)
I,ANGUAGE. PROOF
a,nguage
vill be
donewiúh the
aid ometrical essence,which f calt-,,fiä
ts ngua,ge r{A.fHEÀfATtcA_REvuB D'ANALYSE
NUMÉRTQUE
BT DE THÉORIB
DE
L'APPROXIMATIONL'ANA,LYSE NUMÉRIQUN
ET LA THÉORIE DE
L,APPROXIMATION Tome14, No Z, lghó,
ppi.l7l_t80
t.
.'IIE FUNCTION¡\L, NORtr{AL MITTNG LAN'UA'D7.L. Ilte
signsof
the lønguøgelogical symbols .4 existential quantifier
B disjunction
-C implication
D definition
consúant Þredicates
!,!,
Q,II, K, p,
S,figures o,1 2,
B) 415,6,'
?;ã,' g ä-"å y
L.2.
lormation
rules-Tho figures and letrers are called
signs.-
The numbers areforméd-àith"" of a silgle
figure, ''gures fonowedby n -
1 signs;r",îîu"e
ø isthe
numberN. L. VOLLER 12.
t1l t2) t3l t4l t5j t6l
3l
t8l tsl
t 101
[11]
l12l
I 131
I14l
[15 ]
[16
117
Iìcceivcd 24.1I.1985 Mathemalisches Inslttut dcr
Uniaersiläl DÌlsseldorf UníueLsilüIsstrape I D- 4000 Düsseldorf 1.
U,V L
or of
morefi-
of
figures. The772 ZDLMER Af,.
2
liigures succced
in
reverse ord.eiin
comp_arisonto the
usual rwiting.. rr.or;:11^nt"'
numrrer 12 becomes21y,
nuniberiãz
¡"äåì¡),es|zryy,
and isos an index, an order-number, a varia_
_are
natural
nonzero numbers.ber of
(,-I7"or,
(.D" iff it
isÌó[orved
- A
number.isan
oÌtlerrnumberiff it is
follorvedby tt|ú or
((fu.n,,"or
t.'hD,,) where /¿is
a nurnber,.- Variables are
sequences.-
fndexesare
variaibles.. .
. ,rr-r,##, ',Ii {:;,Toi"lu r',
nz ,. ..,
,'h a,re variabres,then
((ø, nz . . .of
a- scquence, .wc tlo noü takeinto
udcdin other
variables.is
a sequence.P",
bcr of"?qC", "pqllI", "or^" alc
rvff.l,he respe<-rtive
opelation,
a,nri- rf
Pis is
the ¡remberof
(úlrr,.- I1 ni
ø
is
calleclthc ",
ú(rßi" arewff. fn this
case,, _-.: rf u ã : ,:rqii,?t:Piir-,,, ,,n,t¡K,,,
,,nyfr,,,';#.r"
a,rcrvff,
cr of "the;úä;"å
and 31 l,he seconrl j firr ùte variables, Lhert..rrr2
. .. . ¡
ür are
called members-, rrlis
.e_number .of (.D,).
"ptiPq2"
r or
((f-rr).its
basisrn a
wJJany index
equalto a quantifier index is
callecl loose.index of the
quantifier,-
((A)iis a
wff .-
Statementas are wff.-
statements_are numbered. 'r.he order-numberof the
statement.is
precededby a, r, or, (;xióm,ì^ü"o""- or definition).
:3 FUNCTIONAIJ, NORMA¡ WBrlr¡NG LA¡IGUAGE
773
- The
order-numberswhic,I a.e
includedin a statement must
bo Iess l,tranthe
order_numberof
theìiät",r"îîl-
- rn a
stâtement,trre
index,esare,
in-o'.er of their.
appoar¿ùnce,the
nrrmtrer:l, ?, . . (ryìtñ
possiblo repeti[ions;."r qo^otltlu?*lt"-u-tnt, the grìatest i",I;ï;;;;
be equatro
rhe number_ fn a
statemenú,two
clifferen- A 4f is called
asuccessiv"
trdexes.fiel's is the.last sign of ttre tìâl¿ of
¡re
quanti-1,he
forrnula.
sign of*t""t.1, .fT
m be auff
auùn
oneof the following
signs.ft is
calledthc
nr_if
n is 'últt
ot¡ (.1t,ot
(.Zr),ember of
r
úoqeúherwiflr
u-,-i1'r iS ,,1ì,,,, "V"t
(úI'tt. -
with
æ-,if
e;is
,r-Grr, rr7rrr,,..rgrr6¡ rr¡n.
nbcr, tìre variable_mr-lrui, of
, åi"ilr""
s sl;atecl
in ..pq/n.
s sta¿ed
in
..pqX,,.stated
in
r', l,hen ,,pqXD is statedin
r,.re quantifications)
(.p"
rnay be replaced
r
,,21t,) thens
slaterl
in.t.pi.pZ,t.ts
stâ,üe([in
,, pipqZ,, .s stated
in
((piPq2tt.;.
It
inclurledin
an.ycondition
þtia,lin
ù- rr p is
awrr,rhe'
rrre"d;,ïlï;,i lï,".íËJ*]ffi:*'.""t
"'ryerifv that ¡rcre
existsoo
ct6r,,,1,,,i, 1¡,ì--riä"rfri"..",".
a!
twitc-p.
il ;Ht-1"r""'1tÏ1,. t-
n'icfin p tru'ns inLo '(21'
¿rnd.every
,(7,t,, lyici:::W,:'.o" rtic in
b !turns irìto
rr¡'rrald every ((xi, ,,ic in
l¡! t'rns
cZ
! aild
(úf!r,'field. does
not orn
c!
$,hose¿
! add
(31[ttol by (tB" or a quautifior
) FUNCTION.A,L, NORMAL WRMIING LANGUAG{E
1,74 ZELMEn, AT,.
2. PnO()Ì OPtìIl¡tlOItS
4. r75
ú(¡f-lf"
any tinìe it
appears.wll.
is th il: ,1Ë,i:ïHrä#l,iïiLif,::i:ì,Tiî'*1"i,i'f"'il#
sign
of the
formula..
-...pisasqøstarting*ibh l,hei- quantìfier nicin p(ieN*) if forail
j.
NTr-l; <i. <
/c, wheie kis the n
oËerot-qua"tiri-u'"ì, i" i,-ilr"^¡Jl :Ï:*t1]"1 ,r:t.i" p is the
tas.r^.sign.of rhefield of
thej+ 1 ilr-quanrífie',
lt,rc
rt p,
andthe
/u-thquantifier nic in p
isthe last
s"ign of p.1.3.
/
d,etaíled treatise oJ so,nte erøntples ofwrititte
itt, the fultctionul,.trcrntct L wri,ti,tt(t lan,c¡u,øge,
llhc definil,ion z frorn the
/f-spaces t,heorynray be
explessccl asr follor,r's.t-inclucled
in
.I]if antl
onlr.if
for-to 8".
"-4 is
point-
stgns repre-finition,
thec,
ancl ttDtt'"ø
belongsto B"
becomes ,rBZHrr.'úrlo.
ea,chnoint ø belonging
1.oÁ, t) belongs to B"
llecomes, .L32E3PTTITZ'''.(r-4
is
point-includedin l/ if
anlo A,
nbeloigs to
-Bt' becornes r(122. "l-or
aIIA,
B(planes',pgint
r- belongingto A, ab GZIG7'),
rvhichis just
1,he'r'he a,xiom 2 of 1,_.e /i-spaces
theory
is usually forrnulated as follows,'(Fol
cachstraight
linc, ¿r trrereexists only äne point .r
such thal;,r is the beginning of
cli).We note the variables ¿l and ar J¡¡z rrlrr and r.2r) . 'l.herefore ((ø
is the
beginningof
d,r) becoìnes |(ZI(J),.0"""^fn:,;if;lÌF,.""tv
one poinl' ø such i;hatr
is thebeginning
or d))' '(For each straight linc ¿t there exists onlyon
e,beginning. 91_
cl')
becomestZIUZPI LSZ,, aïd,
isof the I12ULP12SZ)).r.ariables according
to
the conditionsimp'o
s.rn an
operationson tre
stal,em:ntshave
been noúedby
ctr, b,
c,.
.,),,_o:.11.!", where!,.,'meanstïaîËåmettring
is addeclto the
ancr '(!"
rneanstrâtiil";;;Ëo-iäïJ""*,.1t or
anorrerindicat
again an¿mã¿itiert. r - --*-
'2.7.
Operatur nl.,,rnI
cxpressesthe function
th¿l,t r.csults fr.oln ,l¿.Yelify that
-..
. r.-th
rlu¿lntificr,of
l¿is
((1r, ¡¡nilln,
t
Ss_ith'thc i_ili quantificr.
,,1r" ol rn, then
foriall j, i< j(
/,,,'a. rvrite m Lill
to
iJrc l'ielcrof
f:hc r-i,hquarrLifitr' crusi'.i *
'l¡.
rv'itc
ûtre intrex r¡nrrrìrc
crornain"i ;i;;;-ìh i"äiìi*,]
"r ,,.
¿'
if
iJre i-th--quan1;ifier of r¿ has" "onaition, iì -i""iïå
in"
conc'titjo' fol- l<¡tvctll)¡' tt-t', if
nol,
g;o bo d.d. rvrite the
fiekl
of the ,i_thqnantifier
oflr.
¿.
\'rite
ú(dtt./.
rvrite rvhat is ief1,in
tn, alte,- 1,he f_flr cluanfiÏiet,.!/'
indexes equarto-the
incre-rof ilrc
r-1;hq'antifier
ofnr
, oth.errvise_replace thcrn..
,), l1i,*,
jr,,,.-.. jr
nt(l;_ n:
e index of tÌre l_ilr cluantifierì of 'li¿. "2.2.
OperatorX
tn,nX
infet'frorn
r¿antl
r¿ l,heir conjunction.ct.
tvtite
m,.Ò'
write
r¿ increasingits
indexcs wil,h flre nurnrrer of qu:r,^tifie.s of ,¿..c.
\ytitetú.,(tt.
îhe t¿sk of this
chapter is language.Ilor this
reasonthe list
anclthe various
operatorsßa¡r
srator
is an algorithrn r.vith the aicl2.3. Operator
1,f,,of
¿ln((ftt.
re exisLs rl e
N
suclr Lltt¡b tt¿ is a s¿rnm a,nd, f h¿r,L bhe fielcl
of this
quanfi- ø.write the first
memberof ilrat
,,.I1".ó.
rvrite l'hat is
lefbin nt
afLi¿t,trÌ,rtrii¡".
¿ ! orclcr the indexes.
2.4. Opera,tor It)
,,_m.iU(í € N*) applics the
s.yrnmetryto t|c rl-th
operatio¡L ú(2,)or
"ÌI" ftom
m.Verif¡'
that' m, contains a1, leasti
operations s(frDor ,,ll[,,.
r¿.
w'ite
mtirl to thc first
rncrnber(e,xcl*si'ely) of the f_tli
opera_tion
(tE1)gy
tc n[tt .t76
D.
rvrite thc
sécontlmembeiof thei-th
operation ...D"or..MD of
m.c. wriùe
the first
memberof the i-th
operation(¡2" or.(M)) of
m.,rl. write the i-th operation ..D" or ,(XIt,
of.lm,.¿.
write
what isleft in
rnafter ttrc i-th
operation ..n))ot ,,M,t
of m..I ! order the
indexes.2.it.
OTterator Jl['ntniir . .
.
'i,,lt,.IW(i
e N8, À; e N,i,
e N) replacesin
n¿the
stretch of ilre.i-th-sign by an
ecluivalentformula'
resurtsfrorn
n¿ rvhen r,eplacing1,he
loose tifier of
tuby the ir-th
vär,iablõ.from the
s
donot countihe
variables rvhichare loose
i
'om 1,he sl,retchof
l,hei-th
sign of m),,where
I is the
numberof quantifiers of
m.Yerify
tha,t-
1,her:-th
si_q*g{*?t i.: ,..,4,,,,,8,,, ,,C,,,,,I),,, ,,p,,, ,,G,,,,,H,,,,
"I"r "¡¡", ((Xf')i (r'N1',
"P"r ",Stt, tl7rr, ti¡ltt, tt'ytt, ts7tt.
- if l, ¡ 0, the
strel,chof the i-th
sign of m, conLainsat
leasl, max(rr ir,.-.
. rià r'ariables rvhich are not looie
inclexcsof the
quantifier,s.from the stretch of the r-tli
signof
ln.- if
/r;#
0, the last /¿ quantifiers of r¿ are ((Zr)àttcl r¿
is a
successive, clrranl,ificationstarting n'ith
t}-]el-lt,),l th quantifier and the field
of-the l-l;flth quantifier of
r¿ endsby
,t-ll{".- il
lc: 0t tt
endsby
,(,44tt.- the
stretch of_th-e'r,-1,h sign ofm
an<\ 1,hefirst
member ofthc
ope-ration
'(JLI_". (indicated_ above)of
r¿ havethe
sarne numberof
quantifiärs, (we notethis
numberl¡y
p).ø
!
rvril,e r¿ increasing eachindex of
iúrvith the number of quanti- fiers of
n¿.?"1
fot all
q_e{!,.2,...,?t\,
r,cplaceflre
loosc indexesof the
q_thrluantifler, from tlie filst
merrl¡erof the
operation .,.M,) Trottt ø Iby'the
inclex
of the q-th
cluantifierfrom the
stretchof the i-th
sign onm.
"c! for all je{l,2,.,.,1.:,\,
r,cplaeethe
loosc indcxesof the
]-- hlitlt
quanbifier from
l¡! by the
r.r-l'h va,r'ial¡lefrorrr the stretch of t¡e í-th
sign of
?
(we do not counl, thc varialrlcs tha1, are loose indexes of the euan-tifiers frorn the strctch of the i-th sign of nt).I)o not .write thc
^basis,of this quantifier
any more,r'erify that
ttre resull,of
1,he su'bstitutioo,"-
complished
in the
basis (rvithout,"z)')
represents one or.t'wo
formulae.(depentlilg-on the type of
cprantification,-simpleor
conclitioned) n'hicl1 are sl,ateclin
ln.Yerify that the first
lnernl¡e,-or "/4''frclrn c!coincides.n'ith
tìre.sl;rrltch
of the i-l,h
signof
m.d
rvrite r¿ replacingthc
sl,retch of thei-ilr
sign oT ntby the
seconcÌ member(of L(Mt)from
c !e
!
orderthe
indexes.2.6,
OperatorIe
.^nz'i7Q
(ie N*¡
suppressesthe condition of the i-tìr q'antifier or
m.Verify that
- m
conl,ains al, leasti
quantifiers.- the i-th quantifier from
r¿has a
condition.ø' rwitc
mtir to
the fielcr ofilie i-th quantifier
excrusively.0.
write thc
condition anclthe
fielcrof ilr" f-th
quanl,ifierof
r¿.¿.
if the
r,-th cluantifierof
/tnis.ta)) ot
(,r)), wr.iie,,x",
andif
iü ist (Z'1
,t rvrite "C",
¿7.
rvrite the
inclex, l,he cromain ancl trre .r-thquantifiel of
rr,.¿.
rvrite
rvhal;is left i' ln
afterthe
i_l,hq..aotifi"".
/! order
1,he indexes.FIINCTIONAI, NONMA¿ WITITING LANGUAGE
2.7. Operator
N
nrÏ
supposesilre contrary of
m,.Vcrrify
that there
existsrìo ,,Ct', (.p), tt¡¡n o.
tnemorize m.Z¡
! rvrite tlie
riegationof
nt,.nlc vI
1n,.ZDLMEn' A[,, Ù ? t77
2.8. Opera,tor c
rm0 recognizes
the
contraclictionof
ø¿.Verif¡'
1¡¿tr-
rz¿ endsby ('xtt
or there existsi
elN*
suchthat
nt, is sclt súartingwith
the^r,--lir Ouqntiliernic
in.m,, boingto"ro"J onijiît'ô"u"tifip¡c ,r/rr
arrd
the field of the i-th
quanbificr n,ic-tnr,
"nãr-¡y',ü''ì:--""""''' - if
rve noteby ¿
thefirst
membel ofthe
operation ((-ytt inclicatc¿a'bove,
there
existsito t'C", (tI)), (tflIr'
,nrcrtt
1t._ by
m_akingthe
neg'ai,ionof
n, follurvccl bJ, increasingthe
inclexesrvith operation'(,Ttt
the number indicatecl above.of
quantiiiersof r,
rvc obtain lJie *"ãã"¿*u*ber
of the ø. rvrite rvhat isin
t,he tnemory (from a pr.cviousìI).
3. ì(-SI"\IJIìS TIIBOTìY
Ilrom
no\\r on rye shall abbrevnition by A., T., D.wlitlen
l,he order-number,
of thc
rcs¿¡ blanl< space, we
rvrite
the sa_rlr,on the
follorvingline,
lea follolysthe proof, wriiten from
,^*^-_ï9
TY-t1,,per-anenilytake
carenot to
confoundthe sig's of ilro
lTgTrffl wlrich
appeaÌonty in
statements,rvith the notatiõn* oi
iüãproor
operators, 'ri'hich appearin the
proofsof the
theorems.178 ZDITMEF, AJ-.
3.I.
Thelist of
s'l,utementslL.7 IZH%1\LI{T,BSIBUZlpZ
4.2 IZUIPIZSZ
T.3 7n-nzItzGr2I{ZrBZ
3U2I!2],8T32].352
T
4.4
72n25r211-22rTnr2L7tr22LrIEXZ1S7,
4.5 I2Iß2VXzSA3PZLPZ
T.6
72U321/X2SI\PZ7PZD.7
7272D32H3P:]IIIZM^G7,|GZ,.8
L282DBZI;BS:I|KZII2GZ\GZD.S
72S2DI272DL282DX]/I2G7.TGZA.}IY
12 n 2G129 2 f)z]:g 2 D,Y 7,7eZ
D
.rry
71ry
7 D23 V 2+ U X + S +1 1t13ñltiIi
I 2 p 2rH Zttl
GZ 4.27Y
I2ÍIN7PZ2G1'l'.31Y
7LIYOL'KNLSZ37 y N 2Ii1
I
T 71 S 21 y ItI
T,y 2Ii
82 I2 S 21 y tr' 2,f,3 1 /S4 2 lr 2 T C,f,.41Y
I2TI1P T27Y OTÍI Z2G Z 2I'y l' 2 1' 4Iy N I Q 1 -D V 22V I1, 2 tL I (
I
(-jT.51y 2ryotr\72D|GZ
+IY 2I'y It \T
Xi
InBt y I22 M 7,t,T',.67y
1 2IflSr2Iy
0 p I( zzq Z:11 y61 t: N I Q\ \tr 22t/ IT 2 + ILX C
I',.7ty 21yOI|I\2D7GZ
67 y 21Y n r7,Y811r31 la 722
It
1'f'?.81L
2lyOr7Ð2D1GZ51 Y71 y
X\
n27 y 11 TX9rn91a
2L2 n[7 TI',
.97J:
r 2 I r 13 ¿/,y3/slì 21 y O p I{ I 2 S22ty
O pIt IL p].zty
Or il z
21v F2 T91y r3r{ 23
Ifi
I +I N 7 Qr T X C 6J 3Jr2 K72K T.02y 2ryo1.r7y7l)
9ly
ztYI
7 T^I1
y L Ð 7 3y 71
MI'I'
T
.rzy rzty
o 1182DLGI27 y OI 7 2DZ
IzY
zLY N T T X 8 92 12 M 7'I' N 21 8 7 2I{T'I
zIYr
T T X 7 g 2L2 M L T 32 T T T 3T S 3 42s31ZL',ILrQzT2+IOI
7'I 2 7 7a Ii- 2'f'
M
2 1, X C 21y?1
1,,y Bt II :lI y 12 2,1[ 7I, T.22y r2tyoTqzDlq7zry
OøLDZtzy
927 yn\
T X22I(I2
I( 3r Zr1'atí2't
72g 7 L S 2Il T.32y
r21 y OntTzDrzty on 92D MrG 7,22y 77Q 9 2t y
I
rr
X22 I{r2 K 3r Z7 T 11 G 7 1' 1 2gI
1' lrQ X7 Il,rzT T.42y
7772DreZtl2Y 7 i¡II2 M N778 C 7 I
ngIt2 ttt
_ rt
goes without_sayingthat
the lisúof
sbal,emen{,sof the
/l-spacestìreory
does no1, encl here.Ilorvevcr, taking into
consicleral,ion th¿r,tt the purposeof this
pa,pelis to
plesent onr. Iang"uage,I
consicler l,hetist
1,o bewide
enough.lj 'i
I FTINCTIONAL, NORMAL WRITÍNG LANGUAG¡' 779
3.2.
Eucnnplesof
proofsTlre proof of the
theorern51Y is +Ly2Iy111L1'XTtEBtyI2ZMIl'
ancl shall be exposed step
by
step. The actionof
each operatoris
shou'nin
detail.+7y t2E1Prztyoruzze7,
2TY
12EN7PZ2GI27YT
û.
b.
2Gc.
2Gd.
ZGLZHNIPZe.
%GTZIINIPZXr. \GLZHNIPZX
a! 2IYOIGI2IYOtr'I{^TII?7'X
h,
! zLvorqtzl yoIHNrPZX 2lyî1I',
e,.
ZIYOEGb. 2lyon'G
r:
! 2lYOnG 4lyzLyntL'1'x
0,. IZHIPI2IYOI'EZZGZ
b. IZI:I|PLZLYOFHZ2GZZIY07'e
(i.
12II7P12IYOtr'IIZ2GZ21yOIt'G^'7
t272D32fI3P31IaZ I[2GZ7GZ 77nü,.
b.
:]2113 P37TIZ(:.
32H3P3IEZ7272I)cL.
|t2HBP37EZI272DMc. 32E3P3IEZI272DM2G7,l
JI 72EII'\3EZ:|272DM2GZ3GZ
4J Y
zIY II
T' X7 IIì:J]-Y I22M
ct,t.
3+HílP:JúHZ5472DM4GZ5 bt
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1,hc stalcrrnont o1l l,he theorem 51Y.it'Ire proof of the theorem 42Y is 42YT\¡IIZMNIIQCTIII9ILZM.
We shall present 1,his
proof
stepb¡'
step indicating 1,he action of each proof operator.+2Y
IL7ZDIGZ,7
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rncrnorizeI2ILIPIZIIZ\GZ
42y75rt2MNLt8 rzHlzENXlIlAzGA
1
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