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A316118 Number of nX3 0..1 arrays with every element unequal to 0, 2, 3, 5, 6 or 7 king-move adjacent elements, with upper left element zero. 1
1, 7, 13, 23, 47, 144, 391, 1118, 3330, 10129, 30953, 95037, 293116, 905585, 2799778, 8662028, 26809369, 82990751, 256933941, 795508636, 2463117879, 7626665518, 23615103348, 73122045417, 226416803035, 701083972797, 2170861196560 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Column 3 of A316123.
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) -7*a(n-3) -10*a(n-4) +7*a(n-5) +24*a(n-6) +20*a(n-7) -38*a(n-8) -69*a(n-9) +22*a(n-10) +115*a(n-11) +43*a(n-12) -92*a(n-13) -56*a(n-14) +18*a(n-15) +16*a(n-16) +4*a(n-17) for n>19
EXAMPLE
Some solutions for n=5
..0..1..0. .0..1..0. .0..1..1. .0..0..1. .0..1..0. .0..1..0. .0..0..0
..0..1..1. .1..1..1. .0..1..1. .0..0..1. .1..1..1. .1..1..0. .0..0..0
..0..1..0. .0..0..0. .0..0..0. .0..0..1. .1..0..1. .0..0..1. .0..0..0
..0..0..0. .0..0..0. .0..1..0. .0..0..1. .0..0..0. .0..1..1. .0..0..0
..1..0..1. .1..1..1. .1..0..1. .0..0..1. .1..1..1. .1..0..0. .1..1..1
CROSSREFS
Cf. A316123.
Sequence in context: A270792 A304671 A075642 * A265766 A228727 A286916
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 24 2018
STATUS
approved

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Last modified June 21 14:19 EDT 2024. Contains 373547 sequences. (Running on oeis4.)