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A072434 Numbers n for which there are exactly ten k such that n = k + reverse(k).

%I A072434 #10 Jul 12 2019 20:18:53
%S A072434 1111,1991,2442,3542,5115,6875,11011,14124,15884,17457,18557,19008,
%T A072434 19091,19291,19491,19691,19891,20091,20291,20491,20691,20891,24042,
%U A072434 24242,24442,24642,24842,25042,25242,25442,25642,25842,34142,34342
%N A072434 Numbers n for which there are exactly ten k such that n = k + reverse(k).
%C A072434 Subsequence of A067030. First term is A072041(10).
%C A072434 Contains 11*10^k+11, 19*10^k+91, 24*10^k+42, 51*10^k+15 for all k>=2. - _Robert Israel_, Jul 12 2019
%H A072434 Robert Israel, <a href="/A072434/b072434.txt">Table of n, a(n) for n = 1..450</a>
%H A072434 <a href="/index/Res#RAA">Index entries for sequences related to Reverse and Add!</a>
%e A072434 2442 = k + reverse(k) for k = 1041, 1131, 1221, 1311, 1401, 2040, 2130, 2220, 2310, 2400.
%p A072434 N:= 10^5:
%p A072434 revdigs:= proc(n) local L,i;
%p A072434   L:= convert(n,base,10);
%p A072434   add(L[-i]*10^(i-1),i=1..nops(L))
%p A072434 end proc:
%p A072434 V:= Vector(N):
%p A072434 for x from 1 to N do
%p A072434   v:= x + revdigs(x);
%p A072434   if v <= N then V[v]:= V[v]+1 fi
%p A072434 od:
%p A072434 select(t -> V[t]=10, [$1..N]); # _Robert Israel_, Jul 12 2019
%o A072434 (ARIBAS) var n,k,c,i,rev: integer; st,nst: string; end; m := 10; for n := 0 to 35000 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 A072434 Cf. A067030, A072041.
%K A072434 base,nonn
%O A072434 1,1
%A A072434 _Klaus Brockhaus_, Jun 17 2002
%E A072434 Offset changed by _Robert Israel_, Jul 12 2019