A318093 Number of nX3 0..1 arrays with every element unequal to 1, 2, 3 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

1, 16, 45, 220, 795, 3310, 12774, 51298, 201637, 802119, 3169137, 12571062, 49748730, 197152806, 780649100, 3092658411, 12248195877, 48517164179, 192162096401, 761151962411, 3014780751286, 11941310147017, 47297795017905

Offset

1,2

Comments

Column 3 of A318098.

Links

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

Formula

Empirical: a(n) = 14*a(n-2) +18*a(n-3) -23*a(n-4) -69*a(n-5) -69*a(n-6) -38*a(n-7) +82*a(n-8) +261*a(n-9) +101*a(n-10) -10*a(n-11) -20*a(n-12) -112*a(n-13) -112*a(n-14) -90*a(n-15) -24*a(n-16) -12*a(n-17) +4*a(n-18) +4*a(n-19) for n>21

Example

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

Crossrefs

Cf. A318098.

Sequence in context: A209993 A322343 A345754 * A223029 A244343 A235772

Adjacent sequences: A318090 A318091 A318092 * A318094 A318095 A318096

Keyword

nonn

Author

R. H. Hardin, Aug 16 2018

Status

approved