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.

1, 2, 2, 4, 16, 4, 8, 208, 208, 8, 16, 3584, 29568, 3584, 16, 32, 76544, 7452704, 7452704, 76544, 32, 64, 1947648, 2941306368, 35704394880, 2941306368, 1947648, 64, 128, 57477120, 1683453629440, 331333877743200, 331333877743200, 1683453629440, 57477120, 128, 256, 1929117696, 1323082429842432, 5338455334819710720, 88366736882654697600, 5338455334819710720, 1323082429842432, 1929117696, 256, 512, 72545402880, 1370418864769445888, 137813651152462288749440

Offset: 1

Author

R. H. Hardin, Oct 25 2003

Keywords

• nonn
• tabl
• nice

Examples

			Array begins:
1,2,4,8,16,32,64,128,256,512,1024,2048,4096,8192,...
2,16,208,3584,76544,1947648,57477120,1929117696...
4,208,29568,7452704,2941306368,1683453629440...
8,3584,7452704,35704394880,331333877743200,...
16,76544,2941306368,331333877743200,...
		

Crossrefs

Cf. A000079 (k = 1 or n = 1), A087518 (n=k). A087923-A087932 give rows 2 through 11. Cf. A007846.

Formula

T(n, k) = T(k, n). T(n, 1) = 2^(n-1) (see A000079).