A231510 Number of nX3 0..1 arrays with no element less than a strict majority of its horizontal, vertical, diagonal and antidiagonal neighbors

4, 14, 78, 343, 1537, 7505, 35872, 168887, 800573, 3806573, 18062200, 85666516, 406536978, 1929318800, 9154739800, 43440293805, 206136096165, 978165298049, 4641595993944, 22025389470655, 104515441789989, 495948930283147

Offset

1,1

Comments

Column 3 of A231515

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +19*a(n-3) +4*a(n-4) -56*a(n-5) -49*a(n-6) -44*a(n-7) -93*a(n-8) +91*a(n-9) -11*a(n-10) +105*a(n-11) +153*a(n-12) +75*a(n-13) +98*a(n-14) +21*a(n-15) +28*a(n-16) for n>17

Example

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

Crossrefs

Sequence in context: A222485 A009347 A341505 * A161132 A186638 A187847

Adjacent sequences: A231507 A231508 A231509 * A231511 A231512 A231513

Keyword

nonn

Author

R. H. Hardin, Nov 09 2013

Status

approved