A305170 Number of nX3 0..1 arrays with every element unequal to 2, 3, 4, 6 or 7 king-move adjacent elements, with upper left element zero.

0, 5, 4, 46, 151, 543, 2120, 8155, 30205, 115292, 437367, 1652127, 6259372, 23720673, 89793169, 340068226, 1288031893, 4877697803, 18472359472, 69958934289, 264942827367, 1003373594916, 3799932457113, 14390883952121, 54500311291862

Offset

1,2

Comments

Column 3 of A305175.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +4*a(n-2) +3*a(n-3) -19*a(n-4) -42*a(n-5) +50*a(n-6) +44*a(n-7) -33*a(n-8) -9*a(n-9) -2*a(n-10) -107*a(n-11) -33*a(n-12) +116*a(n-13) +112*a(n-14) +80*a(n-15) +34*a(n-16) +16*a(n-17) +8*a(n-18)

Example

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

Crossrefs

Cf. A305175.

Sequence in context: A304151 A223527 A262421 * A192344 A181613 A264880

Adjacent sequences: A305167 A305168 A305169 * A305171 A305172 A305173

Keyword

nonn

Author

R. H. Hardin, May 26 2018

Status

approved