A269016 Number of 6Xn binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two exactly once.
0, 420, 4952, 91048, 1053432, 14382480, 164351184, 2008761644, 22653710120, 262438771480, 2922424553104, 32858512559296, 361841100434016, 3993863461953940, 43568235211010040, 474957563309125640
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..0..1..1. .1..0..0..1. .0..1..0..0. .0..0..1..1. .0..1..0..0 ..0..0..0..0. .0..0..1..0. .0..1..0..0. .0..0..0..0. .1..0..0..0 ..1..0..0..1. .1..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..0..0 ..1..0..0..1. .0..0..1..0. .0..0..1..0. .1..0..0..0. .0..0..0..0 ..0..0..0..1. .0..0..0..0. .0..0..0..1. .0..0..1..0. .1..0..1..0 ..0..0..0..0. .1..0..1..0. .0..1..0..1. .0..0..1..0. .1..0..1..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A269011.
Formula
Empirical: a(n) = 8*a(n-1) +160*a(n-2) -980*a(n-3) -9416*a(n-4) +38056*a(n-5) +226410*a(n-6) -670648*a(n-7) -2592568*a(n-8) +5911340*a(n-9) +15294568*a(n-10) -26316136*a(n-11) -50480497*a(n-12) +59619248*a(n-13) +94091288*a(n-14) -64298400*a(n-15) -91176864*a(n-16) +26645760*a(n-17) +36563904*a(n-18) -3642624*a(n-19) -4981824*a(n-20)
Comments