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%I #12 Jul 12 2019 17:46:23
%S 99,110,121,909,929,949,969,989,1009,1010,1029,1030,1049,1050,1069,
%T 1070,1089,1090,1110,1130,1150,1170,1190,1881,2101,3223,4763,9009,
%U 10010,10989,11990,16236,17776,18081,18281,18481,18681,18881,18898
%N Numbers n for which there are exactly nine k such that n = k + reverse(k).
%C Subsequence of A067030. First term is A072041(9).
%C Contains 9*10^k+9 for k>=1 and 10^k+10 for k>=2. - _Robert Israel_, Jul 12 2019
%H Robert Israel, <a href="/A072433/b072433.txt">Table of n, a(n) for n = 1..422</a>
%H <a href="/index/Res#RAA">Index entries for sequences related to Reverse and Add!</a>
%e 99 = k + reverse(k) for k = 18, 27, 36, 45, 54, 63, 72, 81, 90.
%p N:= 10^5:
%p revdigs:= proc(n) local L,i;
%p L:= convert(n,base,10);
%p add(L[-i]*10^(i-1),i=1..nops(L))
%p end proc:
%p V:= Vector(N):
%p for x from 1 to N do
%p v:= x + revdigs(x);
%p if v <= N then V[v]:= V[v]+1 fi;
%p od:
%p select(t -> V[t]=10, [$1..N]); # _Robert Israel_, Jul 12 2019
%o (ARIBAS) var n,k,c,i,rev: integer; st,nst: string; end; m := 9; for n := 0 to 19500 do k := n div 2; c := 0; while k <= n and c < m + 1 do st := itoa(k); nst := ""; for i := 0 to length(st) - 1 do nst := concat(st[i],nst); end; rev := atoi(nst); if n = k + rev then inc(c); if k mod 10 <> 0 and k <> rev then inc(c); end; end; inc(k); end; if c = m then write(n,","); end; end;
%Y Cf. A067030, A072041.
%K base,nonn
%O 1,1
%A _Klaus Brockhaus_, Jun 17 2002
%E Offset changed by _Robert Israel_, Jul 12 2019
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