A304269 Number of n X 7 0..1 arrays with every element unequal to 0, 1, 5 or 8 king-move adjacent elements, with upper left element zero.

21, 23, 67, 259, 1074, 3788, 13767, 53839, 201274, 741275, 2806825, 10575217, 39423977, 147990910, 556562343, 2084799226, 7816395336, 29347218029, 110071768648, 412764006652, 1548711236567, 5809916135249, 21791597835454

Offset

1,1

Comments

Column 7 of A304270.

Links

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

Formula

Empirical: a(n) = a(n-1) +2*a(n-2) +33*a(n-3) +20*a(n-4) -18*a(n-5) -257*a(n-6) -260*a(n-7) -44*a(n-8) +912*a(n-9) +798*a(n-10) +241*a(n-11) -1094*a(n-12) -868*a(n-13) -450*a(n-14) +667*a(n-15) +251*a(n-16) +158*a(n-17) -247*a(n-18) -19*a(n-19) +25*a(n-20) +81*a(n-21) +7*a(n-22) -8*a(n-24) for n>25.

Example

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

Crossrefs

Cf. A304270.

Sequence in context: A303718 A270108 A335189 * A302679 A302514 A303313

Adjacent sequences: A304266 A304267 A304268 * A304270 A304271 A304272

Keyword

nonn

Author

R. H. Hardin, May 09 2018

Status

approved