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A299509
Number of nX3 0..1 arrays with every element equal to 1, 2, 4, 5, 6 or 8 king-move adjacent elements, with upper left element zero.
1
1, 7, 15, 29, 63, 167, 477, 1233, 3265, 8727, 23041, 61427, 163443, 434073, 1154961, 3071109, 8165955, 21718237, 57753279, 153583907, 408435961, 1086155913, 2888454053, 7681365667, 20427272161, 54322941315, 144462750163, 384174434645
OFFSET
1,2
COMMENTS
Column 3 of A299514.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -7*a(n-2) +4*a(n-3) -12*a(n-4) +25*a(n-5) -22*a(n-6) +8*a(n-7) +9*a(n-8) -7*a(n-9) +13*a(n-10) -50*a(n-11) +64*a(n-12) -39*a(n-13) +10*a(n-15) for n>17
EXAMPLE
Some solutions for n=9
..0..1..0. .0..1..0. .0..0..1. .0..1..0. .0..1..0. .0..1..0. .0..1..1
..1..0..1. .1..0..1. .1..1..0. .0..1..0. .1..0..1. .0..1..0. .0..1..0
..0..1..0. .0..0..0. .1..0..1. .0..1..0. .0..1..0. .1..1..1. .1..0..1
..1..1..1. .0..0..0. .0..0..0. .1..1..1. .1..0..1. .1..1..1. .0..0..0
..1..1..1. .0..0..0. .0..0..0. .1..1..1. .0..0..0. .1..1..1. .0..0..0
..1..1..1. .1..0..1. .0..0..0. .1..1..1. .0..0..0. .0..1..0. .0..0..0
..1..1..1. .1..0..1. .0..0..0. .1..1..1. .0..0..0. .1..0..0. .0..0..0
..0..1..0. .1..0..1. .1..0..1. .0..1..0. .1..0..1. .0..0..0. .1..0..1
..0..1..0. .1..0..1. .1..0..1. .1..0..1. .0..1..0. .1..1..0. .1..0..1
CROSSREFS
Cf. A299514.
Sequence in context: A006188 A198589 A298391 * A299309 A300110 A139597
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 11 2018
STATUS
approved