A268762 Number of n X 4 binary arrays with some element plus some horizontally, vertically, diagonally or antidiagonally adjacent neighbor totalling two exactly once.

5, 44, 223, 1148, 5170, 23156, 99057, 418924, 1736105, 7122856, 28898144, 116346184, 465034573, 1848051516, 7306228767, 28758043956, 112751067666, 440538622908, 1715952146561, 6665380161836, 25826102521633, 99840968906384

Offset

1,1

Links

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

Formula

Empirical: a(n) = 4*a(n-1) + 10*a(n-2) - 32*a(n-3) - 47*a(n-4) + 40*a(n-5) + 38*a(n-6) - 12*a(n-7) - 9*a(n-8).

Empirical g.f.: x*(5 + 24*x - 3*x^2 - 24*x^3 - 9*x^4) / (1 - 2*x - 7*x^2 + 2*x^3 + 3*x^4)^2. - Colin Barker, Jan 14 2019

Example

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

Crossrefs

Column 4 of A268766.

Sequence in context: A366650 A271298 A271118 * A068311 A109984 A247776

Adjacent sequences: A268759 A268760 A268761 * A268763 A268764 A268765

Keyword

nonn

Author

R. H. Hardin, Feb 13 2016

Status

approved