A303465 Number of nX4 0..1 arrays with every element equal to 0, 1, 2, 3, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

8, 105, 948, 9110, 89371, 872026, 8511918, 83188773, 812770434, 7941139206, 77594942021, 758189368200, 7408382994582, 72388855049517, 707326301400014, 6911432717332626, 67533080382574931, 659880121609889226

Offset

1,1

Comments

Column 4 of A303469.

Links

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

Formula

Empirical: a(n) = 12*a(n-1) -15*a(n-2) +6*a(n-3) -854*a(n-4) +1079*a(n-5) +2906*a(n-6) +9224*a(n-7) -20608*a(n-8) -22133*a(n-9) -8708*a(n-10) +56172*a(n-11) -22130*a(n-12) -37398*a(n-13) +204184*a(n-14) -19940*a(n-15) +45128*a(n-16) -220512*a(n-17) +7920*a(n-18) -23328*a(n-19) +46656*a(n-20) for n>21

Example

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

Crossrefs

Cf. A303469.

Sequence in context: A302261 A302961 A302804 * A239400 A001922 A264014

Adjacent sequences: A303462 A303463 A303464 * A303466 A303467 A303468

Keyword

nonn

Author

R. H. Hardin, Apr 24 2018

Status

approved