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 A087783 #5 Mar 31 2012 12:35:00 %S A087783 1,2,2,4,16,4,8,208,208,8,16,3584,29568,3584,16,32,76544,7452704, %T A087783 7452704,76544,32,64,1947648,2941306368,35704394880,2941306368, %U A087783 1947648,64,128,57477120,1683453629440,331333877743200,331333877743200,1683453629440,57477120,128,256,1929117696,1323082429842432,5338455334819710720,88366736882654697600,5338455334819710720,1323082429842432,1929117696,256,512,72545402880,1370418864769445888,137813651152462288749440 %N A087783 Array T(n,k) (n >= 1, k >= 1) read by antidiagonals, giving number of ways of arranging the numbers 1 ... mn into an m X n array so there is exactly one local maximum. %F A087783 T(n, k) = T(k, n). T(n, 1) = 2^(n-1) (see A000079). %e A087783 Array begins: %e A087783 1,2,4,8,16,32,64,128,256,512,1024,2048,4096,8192,... %e A087783 2,16,208,3584,76544,1947648,57477120,1929117696... %e A087783 4,208,29568,7452704,2941306368,1683453629440... %e A087783 8,3584,7452704,35704394880,331333877743200,... %e A087783 16,76544,2941306368,331333877743200,... %Y A087783 Cf. A000079 (k = 1 or n = 1), A087518 (n=k). A087923-A087932 give rows 2 through 11. Cf. A007846. %K A087783 nonn,tabl,nice %O A087783 1,2 %A A087783 _R. H. Hardin_, Oct 25 2003