A224408 Number of n X 7 0..1 arrays with rows unimodal and antidiagonals nondecreasing.

29, 267, 1568, 7490, 32814, 139638, 590254, 2496332, 10583872, 44986080, 191565628, 816675452, 3483688120, 14864259432, 63428734440, 270666075032, 1154981259240, 4928419635424, 21029737949696, 89733758819456

Offset: 1

Author

R. H. Hardin, Apr 05 2013

Keywords

• nonn

Comments

Column 7 of A224409.

Examples

			Some solutions for n=3:
..0..0..0..0..0..1..1....1..0..0..0..0..0..0....0..0..0..0..1..0..0
..0..0..0..0..1..1..0....0..0..0..0..0..1..1....0..0..0..1..1..0..0
..1..1..1..1..1..1..1....0..0..0..0..1..1..0....1..1..1..1..1..1..0
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Crossrefs

Cf. A224409.

Formula

Empirical: a(n) = 8*a(n-1) - 20*a(n-2) + 18*a(n-3) - 4*a(n-4) + 2*a(n-5) + 8*a(n-6) + 32*a(n-7) for n>8.

Empirical g.f.: x*(29 + 35*x + 12*x^2 - 236*x^3 - 436*x^4 - 288*x^5 + 116*x^6 + 168*x^7) / (1 - 8*x + 20*x^2 - 18*x^3 + 4*x^4 - 2*x^5 - 8*x^6 - 32*x^7). - Colin Barker, Aug 30 2018