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%I #6 Sep 17 2023 21:35:43
%S 81,16,146,22086,31071113326,365107058344463715696,
%T 2684967738644586785227227090233956040549004,
%U 809079884187716191997158821357206898310718837487307207657194711477350102495950972665
%N a(1) = 81; for n > 1, a(n) is the smallest integer > 0 such that the concatenation a(n)a(n-1)...a(2)a(1) is a square.
%C a(n) = A061359(n+1) for n > 1.
%Y Cf. A061359, A065691, A065791, A065792.
%K base,nonn
%O 1,1
%A _Klaus Brockhaus_, Nov 19 2001