A268884 Number of nX6 binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.

20, 475, 9996, 186732, 3283890, 55491832, 911930096, 14681855846, 232688402028, 3642322709900, 56444213311842, 867475989937560, 13239446101273360, 200865483664370358, 3031934392327858732, 45561723449682618252

Offset: 1

Author

R. H. Hardin, Feb 15 2016

Keywords

• nonn

Comments

Column 6 of A268886.

Examples

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

Links

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

Crossrefs

Cf. A268886.

Formula

Empirical: a(n) = 42*a(n-1) -665*a(n-2) +5138*a(n-3) -21972*a(n-4) +55274*a(n-5) -83769*a(n-6) +76202*a(n-7) -40273*a(n-8) +11304*a(n-9) -1296*a(n-10) for n>12