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.

A297650 Number of nX4 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1, 2 or 3 neighboring 1s.

Original entry on oeis.org

7, 140, 1073, 11024, 113252, 1105531, 11089103, 110654243, 1101808354, 10993719747, 109616866972, 1092971987768, 10899244123139, 108681241877689, 1083722571101531, 10806476047854350, 107757578616646017
Offset: 1

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Author

R. H. Hardin, Jan 02 2018

Keywords

Comments

Column 4 of A297654.

Examples

			Some solutions for n=5
..0..0..0..0. .0..1..1..0. .0..0..0..0. .0..1..0..0. .1..1..0..0
..0..0..0..0. .0..0..1..0. .1..1..1..1. .1..1..0..0. .0..0..0..1
..0..1..1..0. .1..0..1..0. .0..0..0..0. .0..0..1..0. .0..0..1..1
..1..0..1..0. .0..1..0..1. .1..1..0..0. .0..1..0..0. .1..1..1..0
..0..1..1..0. .0..1..1..0. .0..0..1..1. .0..1..1..1. .0..0..0..1
		

Crossrefs

Cf. A297654.

Formula

Empirical: a(n) = 5*a(n-1) +33*a(n-2) +181*a(n-3) -86*a(n-4) -424*a(n-5) -2573*a(n-6) -2524*a(n-7) +335*a(n-8) +9815*a(n-9) +13091*a(n-10) -1385*a(n-11) -21743*a(n-12) -13896*a(n-13) +13557*a(n-14) +25034*a(n-15) +5697*a(n-16) -9754*a(n-17) -8120*a(n-18) +452*a(n-19) +2280*a(n-20) +1082*a(n-21) +210*a(n-22) -30*a(n-23) -12*a(n-24)