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A305906 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4, 5 or 7 king-move adjacent elements, with upper left element zero. 1
4, 14, 35, 98, 358, 1124, 3534, 11667, 37816, 121881, 396149, 1286340, 4168472, 13525005, 43893856, 142389105, 461961170, 1498926869, 4863215164, 15778543522, 51194303437, 166101128424, 538917021528, 1748530951647, 5673154219369 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 3 of A305911.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +4*a(n-2) +11*a(n-3) -19*a(n-4) -49*a(n-5) -54*a(n-6) +80*a(n-7) +161*a(n-8) +107*a(n-9) -128*a(n-10) -154*a(n-11) -22*a(n-12) +37*a(n-13) -26*a(n-14) -33*a(n-15) for n>16
EXAMPLE
Some solutions for n=5
..0..0..1. .0..0..0. .0..0..0. .0..1..0. .0..1..0. .0..1..0. .0..0..0
..1..1..1. .0..0..1. .0..0..0. .0..0..0. .0..0..1. .0..0..0. .0..1..0
..1..1..1. .0..0..0. .0..0..0. .0..0..1. .0..1..1. .0..0..1. .1..0..0
..0..1..1. .0..0..0. .0..0..0. .1..0..0. .0..0..1. .0..0..1. .0..0..0
..0..1..1. .1..1..0. .0..1..1. .0..0..0. .0..1..0. .1..1..1. .0..1..0
CROSSREFS
Cf. A305911.
Sequence in context: A307260 A288678 A295180 * A177110 A213045 A061989
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 14 2018
STATUS
approved

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Last modified March 4 23:31 EST 2024. Contains 370537 sequences. (Running on oeis4.)