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A298631
Number of nX4 0..1 arrays with every element equal to 0, 2, 3, 6 or 7 king-move adjacent elements, with upper left element zero.
1
1, 17, 5, 15, 25, 45, 81, 186, 382, 832, 1778, 3817, 8229, 17739, 38337, 82675, 178602, 385421, 832808, 1798457, 3885412, 8392104, 18129623, 39164407, 84609478, 182786178, 394886144, 853110433, 1843063214, 3981796704, 8602359870
OFFSET
1,2
COMMENTS
Column 4 of A298635.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) -5*a(n-3) +5*a(n-4) -5*a(n-5) -6*a(n-6) +6*a(n-7) +20*a(n-9) -4*a(n-10) -2*a(n-11) -16*a(n-12) -9*a(n-13) +13*a(n-14) +8*a(n-15) +3*a(n-16) -18*a(n-17) -4*a(n-18) +9*a(n-19) -2*a(n-20) +8*a(n-21) -a(n-22) -2*a(n-23) for n>29
EXAMPLE
Some solutions for n=5
..0..0..1..1. .0..1..0..0. .0..0..1..1. .0..0..0..0. .0..0..1..0
..0..1..0..1. .1..1..1..0. .0..1..0..1. .0..1..1..0. .0..1..1..1
..1..0..1..0. .0..0..0..1. .0..1..0..0. .0..1..0..1. .1..0..0..0
..1..0..1..0. .0..1..1..0. .0..1..0..1. .1..0..0..1. .1..1..0..1
..1..1..0..0. .1..1..0..0. .0..0..1..1. .1..1..1..1. .1..0..0..0
CROSSREFS
Cf. A298635.
Sequence in context: A109215 A254070 A297982 * A338559 A243933 A145965
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 23 2018
STATUS
approved