A302960 Number of nX3 0..1 arrays with every element equal to 0, 1, 2, 3 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

4, 29, 154, 833, 4527, 24602, 133757, 727293, 3954552, 21502829, 116922075, 635766762, 3457004649, 18797598113, 102212699104, 555785781065, 3022108386151, 16432841038810, 89354263698021, 485867567617493

Offset

1,1

Comments

Column 3 of A302965.

Links

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

Formula

Empirical: a(n) = 7*a(n-1) -7*a(n-2) -56*a(n-4) +64*a(n-5) for n>6

Example

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

Crossrefs

Cf. A302965.

Sequence in context: A272373 A273247 A302260 * A273300 A300467 A326100

Adjacent sequences: A302957 A302958 A302959 * A302961 A302962 A302963

Keyword

nonn

Author

R. H. Hardin, Apr 16 2018

Status

approved