A268975 Number of 5Xn 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two not more than once.

243, 8448, 114048, 1504656, 18852912, 231730344, 2799406656, 33382885464, 393837138576, 4605236160408, 53449814746368, 616434849399384, 7070720929863408, 80721453100802904, 917737124914636128

Offset: 1

Author

R. H. Hardin, Feb 16 2016

Keywords

• nonn

Comments

Row 5 of A268971.

Examples

			Some solutions for n=3
..1..0..1. .0..2..2. .2..1..2. .0..0..0. .2..1..2. .0..1..2. .0..1..0
..1..2..1. .1..2..1. .0..1..0. .1..0..0. .0..1..0. .0..1..0. .0..0..1
..2..2..2. .1..0..0. .0..1..2. .0..0..0. .2..1..2. .0..0..1. .2..2..2
..1..2..2. .0..0..0. .0..1..2. .1..0..1. .2..2..1. .0..1..0. .1..2..1
..1..1..2. .0..1..0. .2..1..1. .1..0..2. .1..0..0. .0..0..0. .1..2..2
		

Links

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

Crossrefs

Cf. A268971.

Formula

Empirical: a(n) = 32*a(n-1) -384*a(n-2) +2200*a(n-3) -6494*a(n-4) +9016*a(n-5) -816*a(n-6) -14888*a(n-7) +18879*a(n-8) -5464*a(n-9) -7472*a(n-10) +8336*a(n-11) -3648*a(n-12) +768*a(n-13) -64*a(n-14) for n>18