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A278172
Number of nX3 0..1 arrays with every element both equal and not equal to some elements at offset (-1,0) (-1,1) (0,-1) (0,1) (1,-1) or (1,0), with upper left element zero.
1
0, 5, 18, 126, 737, 4551, 27692, 169131, 1032173, 6300804, 38460963, 234775180, 1433121527, 8748112011, 53400529535, 325969389167, 1989793771357, 12146168927085, 74143070289741, 452586729708259, 2762695786609647
OFFSET
1,2
COMMENTS
Column 3 of A278177.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) +11*a(n-2) -22*a(n-3) -31*a(n-4) +32*a(n-5) +47*a(n-6) +22*a(n-7) -17*a(n-8) -77*a(n-9) -73*a(n-10) -52*a(n-11) -37*a(n-12) -8*a(n-13) -a(n-14) +2*a(n-16) for n>18
EXAMPLE
Some solutions for n=4
..0..1..1. .0..0..0. .0..0..0. .0..1..0. .0..1..0. .0..0..0. .0..0..0
..0..0..0. .1..0..1. .1..1..0. .0..1..0. .0..1..0. .1..1..1. .1..1..1
..1..1..1. .1..0..1. .0..1..1. .0..0..0. .0..1..1. .1..0..1. .1..0..1
..0..0..0. .0..0..0. .0..0..1. .1..1..1. .0..0..1. .1..0..0. .0..0..0
CROSSREFS
Cf. A278177.
Sequence in context: A009348 A009365 A140296 * A204252 A281564 A291356
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 13 2016
STATUS
approved