A299684 Number of nX3 0..1 arrays with every element equal to 0, 1, 3, 4, 5, 6 or 7 king-move adjacent elements, with upper left element zero.

3, 4, 15, 54, 156, 854, 3226, 13013, 56318, 229915, 948257, 3968556, 16399773, 67970006, 282408197, 1170437914, 4854200458, 20140780494, 83525093575, 346439146067, 1437039382529, 5960289119226, 24721884651959, 102541799887631

Offset

1,1

Comments

Column 3 of A299689.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +7*a(n-2) +20*a(n-3) -29*a(n-4) -87*a(n-5) -34*a(n-6) +86*a(n-7) +190*a(n-8) -8*a(n-9) -55*a(n-10) -38*a(n-11) +69*a(n-12) -71*a(n-13) -34*a(n-14) +30*a(n-15) for n>17

Example

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

Crossrefs

Cf. A299689.

Sequence in context: A127144 A042771 A176755 * A211182 A135962 A171062

Adjacent sequences: A299681 A299682 A299683 * A299685 A299686 A299687

Keyword

nonn

Author

R. H. Hardin, Feb 16 2018

Status

approved