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 A173488 #7 Jan 02 2020 08:24:07
%S A173488 1,2,4,10,46,426,6816,164778,5561666,248740730,14187451940,
%T A173488 1002045820690,85615117761142,8682866612715706,1029036311254555560,
%U A173488 140656568448867136650,21929110364021381812410,3862525357012048643891882,762298016068721625860646524
%N A173488 Partial sums of A055512.
%C A173488 Partial sums of the number of lattices with n labeled elements. After a(0) = 1, always even, hence the only prime in the partial sum is 2. The subsequence of semiprimes begins 4, 10, 46.
%F A173488 a(n) = Sum_{i=0..n} A055512(i).
%t A173488 Cases[Import["https://oeis.org/A055512/b055512.txt", "Table"], {_, _}][[All, 2]] // Accumulate (* _Jean-François Alcover_, Jan 02 2020 *)
%Y A173488 Cf. A055512, A006966, A001035, Main diagonal of A058159.
%K A173488 nonn,hard,more
%O A173488 0,2
%A A173488 _Jonathan Vos Post_, Feb 19 2010
%E A173488 a(17)-a(18) from _Jean-François Alcover_, Jan 02 2020