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A305284
Number of nX4 0..1 arrays with every element unequal to 1, 2, 3, 4 or 8 king-move adjacent elements, with upper left element zero.
1
2, 86, 279, 1763, 8431, 46983, 246893, 1332201, 7128691, 38238956, 205149469, 1099974489, 5901258508, 31647841376, 169761764249, 910513898513, 4883785069686, 26194911823104, 140501426527538, 753604927279942
OFFSET
1,1
COMMENTS
Column 4 of A305288.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +22*a(n-2) -110*a(n-4) -30*a(n-5) +52*a(n-6) -79*a(n-7) +285*a(n-8) +352*a(n-9) -105*a(n-10) +287*a(n-11) +119*a(n-12) +247*a(n-13) -551*a(n-14) -2706*a(n-15) +416*a(n-16) -844*a(n-17) +717*a(n-18) +2294*a(n-19) -614*a(n-20) +2654*a(n-21) -1250*a(n-22) -1601*a(n-23) +370*a(n-24) -1752*a(n-25) +1971*a(n-26) -572*a(n-27) +251*a(n-28) +191*a(n-29) -489*a(n-30) +410*a(n-31) -282*a(n-32) +191*a(n-33) -72*a(n-34) +23*a(n-35) -6*a(n-36) for n>41
EXAMPLE
Some solutions for n=5
..0..0..1..0. .0..0..0..0. .0..1..0..1. .0..1..0..0. .0..1..0..1
..1..1..1..0. .1..0..0..1. .1..1..1..0. .1..1..1..1. .1..0..0..0
..0..1..1..0. .0..1..1..1. .0..1..1..0. .0..0..1..1. .0..0..0..0
..0..1..1..1. .1..1..1..0. .0..1..1..0. .0..0..0..1. .1..0..0..1
..1..1..0..0. .0..0..0..0. .1..1..1..0. .1..0..0..1. .1..0..1..1
CROSSREFS
Cf. A305288.
Sequence in context: A076542 A226842 A303892 * A304897 A316579 A304593
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 29 2018
STATUS
approved