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A305907
Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 4, 5 or 7 king-move adjacent elements, with upper left element zero.
1
8, 28, 98, 396, 2075, 9140, 40412, 189729, 873060, 3979064, 18356703, 84632174, 389029015, 1791954662, 8257849953, 38030907288, 175204408009, 807291828371, 3719389877395, 17136993336823, 78962057731073, 363828807655049
OFFSET
1,1
COMMENTS
Column 4 of A305911.
FORMULA
Empirical recurrence of order 69 (see link above)
EXAMPLE
Some solutions for n=5
..0..0..0..0. .0..0..0..1. .0..0..1..0. .0..0..1..0. .0..1..0..0
..0..0..0..0. .1..0..0..1. .0..0..0..1. .1..0..0..0. .1..0..0..0
..1..0..0..1. .1..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..0..0
..1..0..0..0. .0..0..0..1. .0..0..0..1. .1..0..0..1. .0..0..1..0
..0..0..0..0. .0..0..0..1. .1..1..0..0. .0..0..0..0. .0..0..0..1
CROSSREFS
Cf. A305911.
Sequence in context: A095857 A184606 A054114 * A110687 A153365 A317149
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 14 2018
STATUS
approved