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%I #9 Jul 12 2019 20:18:37
%S 55,154,505,525,545,565,585,605,625,645,665,685,1414,1434,1441,1454,
%T 1474,1494,1514,1534,1554,1574,1594,2541,5005,6985,14014,14041,14241,
%U 14441,14641,14841,15041,15241,15441,15641,15841,15994,18458,19558
%N Numbers n for which there are exactly five k such that n = k + reverse(k).
%C Subsequence of A067030. First term is A072041(5).
%C Contains 5*(10^k+1) for k>=1. - _Robert Israel_, Jul 12 2019
%H Robert Israel, <a href="/A072429/b072429.txt">Table of n, a(n) for n = 1..254</a>
%H <a href="/index/Res#RAA">Index entries for sequences related to Reverse and Add!</a>
%e 55 = k + reverse(k) for k = 14, 23, 32, 41, 50; 1441 = k + reverse(k) for k = 1040, 1130, 1220, 1310, 1400.
%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]=5, [$1..N]); # Robert Israel, Jul 12 2019
%o (ARIBAS) var n,k,c,i,rev: integer; st,nst: string; end; m := 5; for n := 0 to 24600 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
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