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%I #21 Aug 11 2021 06:59:27
%S 1,225,22201,5555449,111112681,3333330225,555555566736,2222222266944,
%T 33333333393562596,88888888888905609,88888888888905609,
%U 2222222222222640225,2222222222222640225,111111111111119590793871025,5555555555555557064110500049,11111111111111115805344390916
%N Smallest square number starting with (at least) n identical digits.
%C Conjecture: total number of digits of a(n) is always 2*n-1.
%C This conjecture is false: length(a(6)) = 10 != 2*6-1 = 11.
%H Alois P. Heinz, <a href="/A192934/b192934.txt">Table of n, a(n) for n = 1..150</a>
%F a(n) = A119998(n)^2.
%e a(2) = 225 because none of 11, 22, 33, 44, 55, 66, 77, 88, 99, any integer from 110 to 119, or any integer from 220 to 224 is a square, but 15^2 = 225.
%o (PARI) a(n) = {if (n == 1, return (1)); ok = 0; i = 1; while (! ok, i++; d = digits(i^2, 10); if (#d >= n, ok = 1; for (k = 2, n, if (d[k] != d[1], ok = 0; break;);););); return (i^2);} \\ _Michel Marcus_, Jun 14 2013
%Y Cf. A119998, A119511.
%K nonn,base
%O 1,2
%A _J. Lowell_, Aug 25 2011
%E More terms from _Alois P. Heinz_, Sep 02 2011
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