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%I A265152 #9 Oct 13 2017 03:31:41
%S A265152 14,44,89,401,956,6649,17796,58596,432489,4211044,22847241,34268944,
%T A265152 85740489,530152900,718608036,3266783209,33250749225,96733442161,
%U A265152 617288020224,5959324297569,20015258667081,123104551223296,420105398760804,552382701059344,967075372931216
%N A265152 a(1) = 14, a(n) = smallest number > a(n-1) such that the concatenation of a(n-1) and a(n) is a square.
%e A265152 a(3) is 89 since it is the least number greater than a(2)=44 which concatenated with 44 forms a perfect square, i.e., 4489 = 67^2.
%t A265152 f[n_] := Block[{x = n, d = 1 + Floor@ Log10@ n}, q = (Floor@ Sqrt[(10^d + 1) x] + 1)^2; If[q < (10^d) (x + 1), Mod[q, 10^d], Mod[(Floor@ Sqrt[(10^d)(10x + 1) - 1] + 1)^2, 10^(d + 1)] ]]; NestList[f, 14, 24] (* after the algorithm of _David W. Wilson_ in A090566 *)
%Y A265152 Cf. A090566, A265147, A265148, A265149, A265150, A265151, A265153, A265154, A265155.
%K A265152 nonn,base
%O A265152 1,1
%A A265152 _Robert G. Wilson v_, Dec 02 2015

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