A305085 Number of nX4 0..1 arrays with every element unequal to 1, 2, 3, 6 or 7 king-move adjacent elements, with upper left element zero.

2, 33, 34, 91, 352, 372, 1016, 3474, 4945, 13288, 37062, 64155, 165994, 415987, 812826, 2026972, 4818456, 10116447, 24515337, 56876113, 124413665, 295467341, 678580178, 1518490899, 3558083669, 8143158484, 18447074191, 42855072254

Offset

1,1

Comments

Column 4 of A305089.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +6*a(n-3) -31*a(n-4) +6*a(n-5) +10*a(n-6) +73*a(n-7) -15*a(n-8) -70*a(n-9) -42*a(n-10) -6*a(n-11) +63*a(n-12) +32*a(n-13) +12*a(n-14) -25*a(n-15) -20*a(n-16) -3*a(n-17) +4*a(n-18) +4*a(n-19) for n>24

Example

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

Crossrefs

Cf. A305089.

Sequence in context: A304145 A305485 A078732 * A042251 A316736 A199551

Adjacent sequences: A305082 A305083 A305084 * A305086 A305087 A305088

Keyword

nonn

Author

R. H. Hardin, May 25 2018

Status

approved