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 A298119 #14 Feb 16 2025 08:33:53 %S A298119 4,8,8,16,18,16,32,44,44,32,64,114,148,114,64,128,308,548,548,308,128, %T A298119 256,858,2116,2970,2116,858,256,512,2444,8324,16892,16892,8324,2444, %U A298119 512,1024,7074,33028,98466,143224,98466,33028,7074 %N A298119 Array read by antidiagonals: T(m,n) = number of Eulerian orientations of the torus grid graph C_m X C_n. %C A298119 In other words, the number of orientations of the m X n torus grid graph in which each vertex has equal indegree and outdegree. %C A298119 Values are always even since reversing the orientation of each edge will always result in another Eulerian orientation. %H A298119 Andrew Howroyd, <a href="/A298119/b298119.txt">Table of n, a(n) for n = 1..91</a> %H A298119 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/TorusGridGraph.html">Torus Grid Graph</a> %e A298119 Array begins: %e A298119 ============================================================ %e A298119 m\n| 1 2 3 4 5 6 7 %e A298119 ---|-------------------------------------------------------- %e A298119 1 | 4 8 16 32 64 128 256 ... %e A298119 2 | 8 18 44 114 308 858 2444 ... %e A298119 3 | 16 44 148 548 2116 8324 33028 ... %e A298119 4 | 32 114 548 2970 16892 98466 583412 ... %e A298119 5 | 64 308 2116 16892 143224 1250228 11091536 ... %e A298119 6 | 128 858 8324 98466 1250228 16448400 220603364 ... %e A298119 7 | 256 2444 33028 583412 11091536 220603364 4484823396 ... %e A298119 ... %Y A298119 Main diagonal is A054759. %Y A298119 Rows 2..5 are 2*A099754, 2*A170938, A298201, A372093, A372094. %Y A298119 Cf. A212801, A298117. %K A298119 nonn,tabl %O A298119 1,1 %A A298119 _Andrew Howroyd_, Jan 12 2018