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A299556
Number of nX3 0..1 arrays with every element equal to 0, 2, 3, 5, 7 or 8 king-move adjacent elements, with upper left element zero.
1
1, 7, 5, 15, 21, 57, 121, 289, 747, 1901, 5017, 13531, 36501, 99555, 272873, 748887, 2061111, 5679261, 15657685, 43198325, 119216101, 329067269, 908467521, 2508239639, 6925531875, 19123005315, 52804249441, 145810426239, 402636515557
OFFSET
1,2
COMMENTS
Column 3 of A299561.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -5*a(n-2) -5*a(n-3) -2*a(n-4) +20*a(n-5) +9*a(n-6) -39*a(n-7) +18*a(n-8) -10*a(n-9) -41*a(n-10) +83*a(n-11) +26*a(n-12) -44*a(n-13) +7*a(n-14) -9*a(n-15) -17*a(n-16) -3*a(n-17) +6*a(n-18) +2*a(n-19) for n>20
EXAMPLE
Some solutions for n=5
..0..0..0. .0..0..1. .0..0..1. .0..1..0. .0..0..0. .0..1..0. .0..0..1
..0..0..0. .1..0..0. .1..0..0. .0..0..0. .1..0..1. .0..0..0. .1..0..0
..1..1..1. .0..0..1. .0..0..1. .1..0..1. .1..1..1. .1..1..0. .1..1..1
..1..1..1. .1..1..1. .1..0..0. .1..1..1. .0..0..1. .0..1..1. .1..0..1
..1..1..1. .1..0..1. .0..0..1. .0..1..0. .1..0..0. .1..1..0. .0..0..0
CROSSREFS
Cf. A299561.
Sequence in context: A265818 A046557 A298722 * A282978 A125719 A070975
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 12 2018
STATUS
approved