let b be Ordinal; for n being Nat st 0 in Segm n holds
<%(n *^ (exp (omega,b)))%> is Cantor-normal-form
let n be Nat; ( 0 in Segm n implies <%(n *^ (exp (omega,b)))%> is Cantor-normal-form )
assume A1:
0 in Segm n
; <%(n *^ (exp (omega,b)))%> is Cantor-normal-form
set A = <%(n *^ (exp (omega,b)))%>;
A2:
( dom <%(n *^ (exp (omega,b)))%> = Segm 1 & <%(n *^ (exp (omega,b)))%> . 0 = n *^ (exp (omega,b)) )
by AFINSQ_1:def 4;
let a, b be Ordinal; ( a in b & b in dom <%(n *^ (exp (omega,b)))%> implies omega -exponent (<%(n *^ (exp (omega,b)))%> . b) in omega -exponent (<%(n *^ (exp (omega,b)))%> . a) )
assume A3:
a in b
; ( not b in dom <%(n *^ (exp (omega,b)))%> or omega -exponent (<%(n *^ (exp (omega,b)))%> . b) in omega -exponent (<%(n *^ (exp (omega,b)))%> . a) )
assume
b in dom <%(n *^ (exp (omega,b)))%>
; omega -exponent (<%(n *^ (exp (omega,b)))%> . b) in omega -exponent (<%(n *^ (exp (omega,b)))%> . a)
hence
omega -exponent (<%(n *^ (exp (omega,b)))%> . b) in omega -exponent (<%(n *^ (exp (omega,b)))%> . a)
by A3, A2, ORDINAL3:15, TARSKI:def 1; verum