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 A077307 #20 Aug 29 2020 12:52:44
%S A077307 1,1,1,5,5,5,5,5,17,17,17,29,29,29,29,29,35,35,35,47,47,47,47,47,71,
%T A077307 71,71,87,87,87,87,87,99,99,99,123,123,123,123,123,147,147,147,159,
%U A077307 159,159,159,159,167,167,167,191,191,191,191,191,239,239,239,275,275,275,275,275,281,281,281,293
%N A077307 Partial sums of theta series of diamond (A005925).
%F A077307 a(n) = Sum_{i=0..n} A005925(i).
%Y A077307 Cf. A005925.
%K A077307 nonn
%O A077307 0,4
%A A077307 _Jonathan Vos Post_, Dec 13 2010
%E A077307 Incorrect a(16)=35 removed by _Georg Fischer_, Aug 29 2020