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A303041
Number of 3Xn 0..1 arrays with every element equal to 0, 1, 3, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
1
4, 6, 14, 28, 56, 150, 360, 828, 1906, 4628, 10972, 25850, 60948, 145152, 343870, 814072, 1927632, 4573086, 10836712, 25678860, 60851842, 144253956, 341881772, 810275098, 1920403380, 4551789280, 10788216718, 25569422984, 60602792000
OFFSET
1,1
COMMENTS
Row 3 of A303040.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +2*a(n-2) -2*a(n-3) +6*a(n-4) -16*a(n-5) -11*a(n-6) +14*a(n-7) -4*a(n-8) +16*a(n-9) +4*a(n-10) -8*a(n-11) for n>12
EXAMPLE
Some solutions for n=5
..0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..1
..1..1..0..0..0. .0..1..1..1..0. .0..1..0..1..0. .0..1..0..0..0
..0..1..0..1..0. .0..1..0..1..0. .0..1..1..1..0. .0..1..1..1..0
CROSSREFS
Cf. A303040.
Sequence in context: A030138 A369684 A009849 * A103419 A005202 A342602
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 17 2018
STATUS
approved