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 A066552 #4 Dec 05 2013 19:55:05
%S A066552 1,13,9,18,28,5,26,37,38,34,61,59,43,58,44,64,44,59,67,85,98,89,109,
%T A066552 121,124,144,47,82,94,104,135,139,145,103,95,135,184,162,143,173,157,
%U A066552 151,198,194,199,218,148,234,231,261,257,226,297,169,192,179,163,195,216
%N A066552 Sum of digits of n-th term of A066551.
%t A066552 With[{c=Flatten[IntegerDigits/@(Range[400]^2)]},Table[Total[Take[c,{(n(n-1))/2+1,(n(n-1))/2+n}]],{n,60}]] (* _Harvey P. Dale_, Jul 21 2012 *)
%Y A066552 Cf. A066547, A066549, A066551.
%K A066552 nonn,base
%O A066552 1,2
%A A066552 _Amarnath Murthy_, Dec 16 2001
%E A066552 More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 01 2003