A297734 Number of 2Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 2 or 4 neighboring 1s.

1, 2, 8, 15, 32, 61, 145, 297, 658, 1352, 2975, 6240, 13565, 28609, 61801, 131106, 282136, 600239, 1288448, 2746557, 5887025, 12563881, 26904370, 57460200, 122975935, 262760096, 562158461, 1201484193, 2569940969, 5493595714

Offset

1,2

Comments

Row 2 of A297733.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +a(n-2) -3*a(n-3) +6*a(n-4) -6*a(n-5)

Example

Some solutions for n=7
..1..1..1..1..0..1..0. .0..1..0..0..0..0..0. .0..1..1..1..1..1..0
..0..1..0..1..1..1..1. .1..1..1..0..0..0..0. .0..1..1..1..1..1..0

Crossrefs

Cf. A297733.

Sequence in context: A189952 A077598 A095298 * A100596 A295937 A305674

Adjacent sequences: A297731 A297732 A297733 * A297735 A297736 A297737

Keyword

nonn

Author

R. H. Hardin, Jan 04 2018

Status

approved