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%I #5 Aug 20 2019 11:18:23
%S 768,859,911,3286,6714,45453,54547,990101,8181820,70588234,343130555,
%T 362637364,363636362,420053632,421052633,497975710,502024290,
%U 578947367,579946368,636363638,637362636,656869445,706766919
%N n times n+1 gives the concatenation of two numbers m and m+2.
%H Robert Israel, <a href="/A116301/b116301.txt">Table of n, a(n) for n = 1..9000</a>
%p As:= {}:
%p for m from 2 to 20 do
%p acands:= map(t -> rhs(op(t)), [msolve(a*(a+1)=2, 10^m+1)]);
%p bcands:= map(t -> t*(t+1) mod 10^m, acands);
%p good:= select(t -> bcands[t]>=10^(m-1), [$1..nops(acands)]);
%p As:= As union convert(acands[good],set);
%p od:
%p sort(convert(As,list)); # _Robert Israel_, Aug 20 2019
%Y Cf. A116170, A116294, A116302, A116307.
%K nonn,base
%O 1,1
%A _Giovanni Resta_, Feb 06 2006
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