This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A065691 #5 Sep 17 2023 21:33:29 %S A065691 0,10,8,16,146,22086,31071113326,365107058344463715696, %T A065691 2684967738644586785227227090233956040549004, %U A065691 809079884187716191997158821357206898310718837487307207657194711477350102495950972665 %N A065691 a(1) = 0; 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 A065691 a(n) = A061359(n-1) for n > 2. %Y A065691 Cf. A050634, A050635, A061359, A065689, A065690. %K A065691 base,nonn %O A065691 1,2 %A A065691 _Klaus Brockhaus_, Nov 17 2001