A268890 Number of 5Xn binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.

0, 235, 2418, 31956, 317966, 3283890, 31427480, 299524050, 2777161184, 25505113994, 231143340184, 2077724593805, 18526267129268, 164165431218906, 1446558738555296, 12686251671077220, 110791183092125102

Offset: 1

Author

R. H. Hardin, Feb 15 2016

Keywords

• nonn

Comments

Row 5 of A268886.

Examples

			Some solutions for n=4
..1..1..0..1. .1..0..0..0. .1..0..1..1. .1..0..0..0. .1..0..1..0
..0..1..0..1. .0..0..0..1. .1..0..0..0. .0..0..0..1. .1..0..0..0
..0..1..0..0. .1..0..0..0. .1..0..0..0. .1..1..0..1. .0..0..1..1
..0..0..0..1. .1..0..0..0. .0..0..0..0. .0..0..0..1. .1..0..0..1
..0..1..0..0. .1..0..1..1. .0..0..0..1. .0..0..0..1. .0..0..0..0
		

Links

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

Crossrefs

Cf. A268886.

Formula

Empirical: a(n) = 2*a(n-1) +97*a(n-2) +116*a(n-3) -2923*a(n-4) -10986*a(n-5) +4951*a(n-6) +72992*a(n-7) +36740*a(n-8) -223968*a(n-9) -159382*a(n-10) +423052*a(n-11) +256370*a(n-12) -539504*a(n-13) -176570*a(n-14) +450908*a(n-15) +6166*a(n-16) -217920*a(n-17) +57416*a(n-18) +45120*a(n-19) -25021*a(n-20) +562*a(n-21) +2089*a(n-22) -388*a(n-23) -31*a(n-24) +14*a(n-25) -a(n-26)