A298050 Number of nX3 0..1 arrays with every element equal to 1, 2, 4 or 6 king-move adjacent elements, with upper left element zero.

1, 7, 15, 19, 23, 34, 63, 96, 147, 233, 368, 588, 933, 1500, 2404, 3842, 6157, 9887, 15907, 25577, 41128, 66175, 106524, 171543, 276293, 445096, 717116, 1155533, 1862256, 3001558, 4838268, 7799411, 12573667, 20271639, 32684289, 52699948

Offset

1,2

Comments

Column 3 of A298055.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) -a(n-2) -2*a(n-3) -3*a(n-5) +3*a(n-6) +3*a(n-7) -a(n-8) +2*a(n-9) +6*a(n-10) -8*a(n-11) -3*a(n-12) -4*a(n-13) -2*a(n-14) +4*a(n-15) +8*a(n-16) -a(n-17) -3*a(n-18) for n>19

Example

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

Crossrefs

Cf. A298055.

Sequence in context: A224891 A138641 A297853 * A115783 A140109 A064397

Adjacent sequences: A298047 A298048 A298049 * A298051 A298052 A298053

Keyword

nonn

Author

R. H. Hardin, Jan 11 2018

Status

approved