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.

A189612 Number of n X 4 binary arrays without the pattern 0 1 0 diagonally, antidiagonally or horizontally.

Original entry on oeis.org

12, 144, 1164, 8496, 65160, 515560, 4075336, 32031600, 251533888, 1976926440, 15543816656, 122208548968, 960755182696, 7553047614920, 59379727197728, 466827426445200, 3670067881137352, 28853031765433504, 226834374728410104
Offset: 1

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Author

R. H. Hardin, Apr 24 2011

Keywords

Comments

Column 4 of A189617.

Examples

			Some solutions for 3 X 4
..1..1..1..1....0..1..1..0....1..1..0..0....1..0..0..0....1..1..1..0
..1..1..0..1....1..1..0..1....1..1..1..0....1..0..1..1....0..1..1..0
..0..0..1..1....1..0..1..1....1..1..1..0....1..1..0..1....0..1..1..1
		

Crossrefs

Cf. A189617.

Formula

Empirical: a(n) = 12*a(n-1) -29*a(n-2) -69*a(n-3) +512*a(n-4) -1626*a(n-5) +60*a(n-6) +9924*a(n-7) -9708*a(n-8) +1120*a(n-9) +1064*a(n-10) -73360*a(n-11) +46560*a(n-12) +40960*a(n-13) +31616*a(n-14) +147456*a(n-15) -64000*a(n-16) -110592*a(n-17) -16384*a(n-18) -32768*a(n-19).