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A305336 Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 5 or 8 king-move adjacent elements, with upper left element zero. 1
8, 9, 26, 81, 267, 938, 3186, 10840, 37115, 127093, 434701, 1487032, 5088052, 17408881, 59562461, 203788091, 697249613, 2385595861, 8162156545, 27926287144, 95547994595, 326911280365, 1118505753468, 3826895020494, 13093473621594 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 4 of A305340.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +5*a(n-2) +a(n-3) -11*a(n-5) -24*a(n-6) +5*a(n-7) +17*a(n-8) -5*a(n-9) +6*a(n-10) +14*a(n-11) -5*a(n-12) -10*a(n-13) +2*a(n-14) +4*a(n-15) for n>19
EXAMPLE
Some solutions for n=5
..0..0..0..0. .0..1..0..0. .0..1..0..0. .0..1..0..0. .0..0..1..0
..0..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..0..0. .1..0..0..0
..0..0..0..0. .0..0..0..0. .0..0..0..0. .0..1..0..0. .0..0..0..0
..0..1..0..1. .0..0..0..0. .0..0..1..1. .0..0..0..1. .0..1..0..1
..0..0..0..0. .0..1..0..0. .0..0..1..1. .0..0..0..0. .0..0..0..0
CROSSREFS
Cf. A305340.
Sequence in context: A041134 A108219 A041317 * A042311 A371629 A003997
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 30 2018
STATUS
approved

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Last modified July 18 15:51 EDT 2024. Contains 374388 sequences. (Running on oeis4.)