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 A143123 #10 Aug 28 2020 06:06:43
%S A143123 1,2,6,16,42,101,241,548,1232,2696,5818,12318,25744,52992,107796,
%T A143123 216598,430669,847518,1652642,3194279,6124608,11653341,22015653,
%U A143123 41310879,77024333,142739427,262996080,481889660,878308359,1592707740
%N A143123 a(n) = Sum_{j=0..n} A000293(j).
%e A143123 a(3) = 16 = (1 + 1 + 4 + 10).
%Y A143123 Cf. A000293.
%K A143123 nonn
%O A143123 0,2
%A A143123 _Gary W. Adamson_, Jul 26 2008
%E A143123 a(11) corrected and more terms from _Georg Fischer_, Aug 28 2020