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A304851
Number of nX4 0..1 arrays with every element unequal to 0, 1, 3, 4 or 7 king-move adjacent elements, with upper left element zero.
1
5, 17, 15, 38, 65, 127, 264, 626, 1369, 3086, 7163, 16749, 38635, 90513, 214590, 507478, 1197982, 2840209, 6749471, 16027442, 38068309, 90532903, 215399198, 512410252, 1219160697, 2901582764, 6906265462, 16437956844, 39127612253
OFFSET
1,1
COMMENTS
Column 4 of A304855.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -8*a(n-2) +4*a(n-3) +8*a(n-4) -35*a(n-5) +57*a(n-6) -24*a(n-7) -87*a(n-8) +154*a(n-9) -134*a(n-10) +120*a(n-11) +163*a(n-12) -369*a(n-13) +430*a(n-14) -288*a(n-15) -172*a(n-16) +223*a(n-17) -1201*a(n-18) +574*a(n-19) +229*a(n-20) -123*a(n-21) +916*a(n-22) +417*a(n-23) +1047*a(n-24) +18*a(n-25) -834*a(n-26) -591*a(n-27) -851*a(n-28) -687*a(n-29) -257*a(n-30) +188*a(n-31) +500*a(n-32) +418*a(n-33) +177*a(n-34) +96*a(n-35) +30*a(n-36) -50*a(n-37) -84*a(n-38) -46*a(n-39) +4*a(n-41) for n>44
EXAMPLE
Some solutions for n=5
..0..0..0..1. .0..0..1..1. .0..0..0..0. .0..0..0..1. .0..0..0..0
..0..0..0..0. .0..0..0..1. .1..0..0..1. .0..0..0..0. .0..0..0..1
..0..0..1..1. .0..0..0..0. .0..1..1..0. .0..0..0..0. .0..0..1..1
..0..0..0..0. .0..0..0..0. .1..1..1..1. .0..0..0..1. .0..1..1..1
..0..1..1..0. .1..0..0..0. .1..1..1..1. .0..0..1..1. .1..1..1..1
CROSSREFS
Cf. A304855.
Sequence in context: A302631 A303678 A303804 * A237437 A128895 A141558
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 19 2018
STATUS
approved