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 A085503 #28 Aug 31 2021 04:22:23
%S A085503 1,1,1,1,66,1,1,1191,1191,1,1,14608,156190,14608,1,1,152637,9738114,
%T A085503 9738114,152637,1,1,1479726,423281535,2275172004,423281535,1479726,1,
%U A085503 1,13824739,15041229521,311387598411
%N A085503 Sub-triangle of A008292: take every second term of every second row.
%H A085503 Claire Levaillant, <a href="https://arxiv.org/abs/2001.03471">Powers of two weighted sum of the first p divided Bernoulli numbers modulo p</a>, arXiv:2001.03471 [math.CO], 2020. See p. 6.
%e A085503 {1},
%e A085503 {1, 1},
%e A085503 {1, 66, 1},
%e A085503 {1, 1191, 1191, 1},
%e A085503 {1, 14608, 156190, 14608, 1},
%e A085503 {1, 152637, 9738114, 9738114, 152637, 1},
%t A085503 << DiscreteMath`Combinatorica`
%t A085503 a = Table[Table[Eulerian[n + 1, 2*m], {m, 0, Floor[n/2]}], {n, 0, 20, 2}];
%t A085503 Flatten[%]
%Y A085503 Cf. A008292.
%K A085503 nonn,tabl
%O A085503 0,5
%A A085503 _Roger L. Bagula_, Dec 13 2010