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 A002440 M3431 N1392 #23 Jul 02 2025 16:01:54
%S A002440 1,4,12,22,34,51,100,121,144,202,232,264,331,400,441,514,562,642,1024,
%T A002440 1111,1200,1261,1354,1452,1552,1654,2061,2200,2311,2424,2542,2662,
%U A002440 3114,3241,3400,3531,3664,4132,4302,4444,4621,5100,5251,5434,5622,6112,6304
%N A002440 Squares written in base 7.
%C A002440 Squares in base 10: 1, 4, 100, 121, 144, 400, 441, 1024, 10000, 10201, 10404, 12100, 12321, 12544, 14400, 14641. - _Zak Seidov_, Apr 18 2014
%D A002440 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D A002440 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%D A002440 V. Thébault, Les Récréations Mathématiques. Gauthier-Villars, Paris, 1952, p. 93.
%H A002440 Zak Seidov, <a href="/A002440/b002440.txt">Table of n, a(n) for n = 1..1000</a>
%F A002440 a(n) = A007093(A000290(n)). - _Jason Kimberley_, Dec 13 2012
%t A002440 Table[FromDigits[IntegerDigits[n^2, 7]], {n, 100}] (* _Zak Seidov_, Apr 18 2014 *)
%K A002440 nonn,base,easy
%O A002440 1,2
%A A002440 _N. J. A. Sloane_
%E A002440 More terms from _James Sellers_, Sep 08 2000