A224406 Number of n X 5 0..1 arrays with rows unimodal and antidiagonals nondecreasing.

16, 101, 465, 1928, 7812, 31710, 129402, 529846, 2172346, 8908986, 36534670, 149811438, 614276002, 2518688490, 10327233902, 42344211246, 173621959826, 711894378346, 2918949452350, 11968441441998, 49073678703842

Offset

1,1

Comments

Column 5 of A224409.

Links

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

Formula

Empirical: a(n) = 6*a(n-1) - 9*a(n-2) + 4*a(n-3) + 2*a(n-4) + 8*a(n-5).

Empirical g.f.: x*(1 - x)*(16 + 21*x + 24*x^2 + 7*x^3) / (1 - 6*x + 9*x^2 - 4*x^3 - 2*x^4 - 8*x^5). - Colin Barker, Aug 30 2018

Example

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

Crossrefs

Cf. A224409.

Sequence in context: A223767 A223774 A224155 * A223016 A253390 A264281

Adjacent sequences: A224403 A224404 A224405 * A224407 A224408 A224409

Keyword

nonn

Author

R. H. Hardin, Apr 05 2013

Status

approved