A304896 Number of nX3 0..1 arrays with every element unequal to 1, 2, 3, 4 or 7 king-move adjacent elements, with upper left element zero.

1, 23, 62, 330, 1249, 5562, 23101, 99064, 418753, 1782180, 7560125, 32121500, 136371438, 579184407, 2459401732, 10444343450, 44352084495, 188345794820, 799822302052, 3396512040540, 14423538367155, 61250684689212

Offset

1,2

Comments

Column 3 of A304901.

Links

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

Formula

Empirical: a(n) = a(n-1) +12*a(n-2) +11*a(n-3) -12*a(n-4) -15*a(n-5) +14*a(n-6) +14*a(n-7) +26*a(n-8) +5*a(n-9) +a(n-10) -a(n-11) -17*a(n-12) +a(n-13) -5*a(n-14) +2*a(n-15) for n>16

Example

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

Crossrefs

Cf. A304901.

Sequence in context: A232235 A107692 A089823 * A316578 A323220 A001346

Adjacent sequences: A304893 A304894 A304895 * A304897 A304898 A304899

Keyword

nonn

Author

R. H. Hardin, May 20 2018

Status

approved