A231525 Number of 3Xn 0..1 arrays with no element less than a strict majority of its horizontal, diagonal and antidiagonal neighbors

8, 21, 153, 865, 4665, 25556, 144847, 817539, 4574717, 25577718, 143371820, 804082832, 4506873305, 25254564785, 141534685147, 793277267583, 4446076119277, 24918173471356, 139655004825056, 782709245520654

Offset

1,1

Comments

Row 3 of A231523

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 6*a(n-1) -8*a(n-2) +29*a(n-3) +56*a(n-4) -182*a(n-5) -17*a(n-6) -559*a(n-7) -759*a(n-8) +476*a(n-9) +377*a(n-10) +965*a(n-11) +1048*a(n-12) -43*a(n-13) +15*a(n-14) -384*a(n-15) -335*a(n-16) for n>17

Example

Some solutions for n=7
..0..0..0..0..1..1..1....0..0..0..0..1..1..0....0..0..0..0..1..1..0
..0..0..1..0..0..0..0....0..0..0..1..0..0..1....0..1..0..0..0..0..0
..1..0..0..0..0..0..0....1..1..0..0..0..0..1....0..0..0..0..1..0..0

Crossrefs

Sequence in context: A100903 A358720 A240648 * A228756 A228504 A270552

Adjacent sequences: A231522 A231523 A231524 * A231526 A231527 A231528

Keyword

nonn

Author

R. H. Hardin, Nov 10 2013

Status

approved