login
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
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
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 20 2018
STATUS
approved