cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A268786 Number of nX5 binary arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two exactly once.

Original entry on oeis.org

10, 131, 1144, 9085, 67100, 477128, 3295246, 22302699, 148575958, 977609634, 6368239274, 41140907455, 263939673228, 1683296018391, 10680625988516, 67468330344536, 424526386272378, 2661981983940811, 16640406499054332
Offset: 1

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Author

R. H. Hardin, Feb 13 2016

Keywords

Comments

Column 5 of A268789.

Examples

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

Crossrefs

Cf. A268789.

Formula

Empirical: a(n) = 2*a(n-1) +41*a(n-2) +54*a(n-3) -509*a(n-4) -2182*a(n-5) -2830*a(n-6) +1766*a(n-7) +7914*a(n-8) +2584*a(n-9) -10583*a(n-10) -6092*a(n-11) +11506*a(n-12) +5348*a(n-13) -11688*a(n-14) -620*a(n-15) +9251*a(n-16) -4462*a(n-17) -3137*a(n-18) +4774*a(n-19) -2365*a(n-20) +338*a(n-21) +198*a(n-22) -106*a(n-23) +12*a(n-24) +4*a(n-25) -a(n-26)