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A305092 Number of nX3 0..1 arrays with every element unequal to 1, 2, 4, 6 or 7 king-move adjacent elements, with upper left element zero. 1
1, 9, 14, 17, 64, 158, 229, 630, 1626, 2950, 6627, 16872, 34743, 73749, 177939, 391569, 832239, 1918128, 4326797, 9358621, 21010056, 47538986, 104476103, 232064401, 522612729, 1159790910, 2570796250, 5758552148, 12835315322, 28485986767 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Column 3 of A305097.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-2) +11*a(n-3) +7*a(n-4) -16*a(n-5) -46*a(n-6) -31*a(n-7) +27*a(n-8) +64*a(n-9) +38*a(n-10) -20*a(n-11) -25*a(n-12) -6*a(n-13) +7*a(n-14) +a(n-15) -2*a(n-16) for n>17
EXAMPLE
Some solutions for n=5
..0..0..1. .0..1..1. .0..0..1. .0..1..0. .0..1..0. .0..0..1. .0..0..0
..0..1..0. .1..0..1. .0..1..0. .1..0..0. .1..0..0. .1..1..1. .0..1..1
..0..0..0. .1..1..1. .0..0..0. .0..0..0. .1..1..0. .1..1..1. .0..0..0
..0..1..0. .1..0..1. .0..0..0. .0..1..0. .1..0..1. .1..0..1. .0..1..1
..0..0..1. .1..0..1. .0..1..1. .0..1..0. .1..1..1. .1..0..1. .0..0..0
CROSSREFS
Cf. A305097.
Sequence in context: A217005 A103409 A011767 * A205690 A328246 A244466
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 25 2018
STATUS
approved

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)