A302742 Number of 3Xn 0..1 arrays with every element equal to 0, 1, 2, 3 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

4, 32, 228, 1637, 11814, 85268, 615589, 4444226, 32085336, 231641898, 1672352613, 12073650477, 87166448968, 629303444781, 4543294244531, 32800587324576, 236805822155030, 1709633941974433, 12342805548255732, 89109630466361141

Offset

1,1

Comments

Row 3 of A302741.

Links

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

Formula

Empirical: a(n) = 7*a(n-1) +4*a(n-2) -17*a(n-3) -3*a(n-4) -9*a(n-6) +14*a(n-7) for n>8

Example

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

Crossrefs

Cf. A302741.

Sequence in context: A125823 A320366 A317560 * A300210 A302736 A033515

Adjacent sequences: A302739 A302740 A302741 * A302743 A302744 A302745

Keyword

nonn

Author

R. H. Hardin, Apr 12 2018

Status

approved