A299888 Number of n X 3 0..1 arrays with every element equal to 0, 2, 3, 4, 5, 7 or 8 king-move adjacent elements, with upper left element zero.

1, 13, 31, 156, 614, 2800, 13379, 63697, 313055, 1541446, 7631089, 37907371, 188460970, 938008699, 4670538813, 23261346000, 115871179617, 577226703607, 2875668407886, 14326569827639, 71375895052167, 355602303531952

Offset

1,2

Comments

Column 3 of A299893.

Links

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

Formula

Empirical: a(n) = 6*a(n-1) +2*a(n-2) -33*a(n-3) -40*a(n-4) +152*a(n-5) +18*a(n-6) -368*a(n-7) +310*a(n-8) +492*a(n-9) -362*a(n-10) -290*a(n-11) -8*a(n-12) -12*a(n-13) for n>15.

Example

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

Crossrefs

Cf. A299893.

Sequence in context: A007628 A335787 A141837 * A023304 A247837 A346022

Adjacent sequences: A299885 A299886 A299887 * A299889 A299890 A299891

Keyword

nonn

Author

R. H. Hardin, Feb 21 2018

Status

approved