A303184 Number of 4Xn 0..1 arrays with every element equal to 0, 1, 2, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

8, 81, 135, 297, 931, 2569, 6668, 17934, 48674, 131037, 353419, 953231, 2569308, 6928326, 18683550, 50378075, 135840557, 366289949, 987683660, 2663241442, 7181313510, 19364081749, 52214352523, 140793629575, 379643605448

Offset

1,1

Comments

Row 4 of A303182.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) -4*a(n-2) +4*a(n-3) -9*a(n-4) +6*a(n-5) -5*a(n-6) +4*a(n-7) -4*a(n-8) +14*a(n-9) -9*a(n-10) -2*a(n-12) +8*a(n-13) +2*a(n-14) -8*a(n-15) -4*a(n-16) +4*a(n-17) for n>22

Example

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

Crossrefs

Cf. A303182.

Sequence in context: A301939 A302417 A227227 * A302325 A303018 A247536

Adjacent sequences: A303181 A303182 A303183 * A303185 A303186 A303187

Keyword

nonn

Author

R. H. Hardin, Apr 19 2018

Status

approved