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%I #14 Jul 17 2018 08:57:39
%S 9,99,146,999,3701,8881,9999,10512,13088,13271,13466,15625,49547,
%T 50502,60146,73398,85941,99999,155613,205062,513335,712539,999999,
%U 1005012,1060146,1334666,3990487,5005002,9999999,20050062,26930824,39341318,46022544,58331666,63116013
%N Numbers k not ending in zero that are a substring of k*(k+1).
%C A002283 is a subset of this sequence.
%C Contains 5*10^(2*m)+5*10^m+2 and 2*10^(2*m+1)+5*10^(m+1)+62 for m >= 2. - _Robert Israel_, Jun 29 2018
%H Giovanni Resta, <a href="/A305670/b305670.txt">Table of n, a(n) for n = 1..90</a>
%e 13088 * 13089 = 171308832;
%e 13271 * 13272 = 176132712.
%p P:=proc(q) local k,n; for n from 1 to q do if n mod 10>0 then
%p for k from 1 to ilog10(n*(n+1))-ilog10(n)+1 do
%p if n=trunc(n*(n+1)/10^(k-1)) mod 10^(ilog10(n)+1) then print(n);
%p break; fi; od; fi; od; end: P(10^8);
%Y Cf. A002283, A316263.
%K nonn,base
%O 1,1
%A _Paolo P. Lava_, Jun 28 2018
%E Edited by _Robert Israel_, Jun 29 2018
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