A302261 Number of nX4 0..1 arrays with every element equal to 0, 1, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

8, 105, 772, 5922, 45717, 353229, 2727755, 21069318, 162753849, 1257225302, 9711792270, 75021745843, 579529894725, 4476770505137, 34582309009590, 267142643360807, 2063633101348406, 15941227812038514, 123143376763267969

Offset

1,1

Comments

Column 4 of A302265.

Links

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

Formula

Empirical: a(n) = 9*a(n-1) -2*a(n-2) -51*a(n-3) -80*a(n-4) -11*a(n-5) +262*a(n-6) +1203*a(n-7) -73*a(n-8) -847*a(n-9) -3807*a(n-10) +103*a(n-11) -606*a(n-12) +4295*a(n-13) +1436*a(n-14) +1630*a(n-15) -3052*a(n-16) +576*a(n-17) for n>18

Example

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

Crossrefs

Cf. A302265.

Sequence in context: A285745 A119934 A247537 * A302961 A302804 A303465

Adjacent sequences: A302258 A302259 A302260 * A302262 A302263 A302264

Keyword

nonn

Author

R. H. Hardin, Apr 04 2018

Status

approved