A231941 Number of 2 X n 0..3 arrays with no element less than a strict majority of its horizontal, diagonal and antidiagonal neighbors.

16, 84, 668, 5070, 42104, 326010, 2511252, 19430715, 152135920, 1190465282, 9289762532, 72404777123, 564819519982, 4409093385085, 34418864675001, 268626308705377, 2096420912100320, 16362151427663928, 127710770440282286

Offset

1,1

Comments

Row 2 of A231940.

Links

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

Formula

Empirical: a(n) = 16*a(n-1) -86*a(n-2) +190*a(n-3) +319*a(n-4) -4988*a(n-5) +10423*a(n-6) +3869*a(n-7) -14328*a(n-8) +132748*a(n-9) -44748*a(n-10) -130980*a(n-11) -63336*a(n-12) -493560*a(n-13) -373248*a(n-14) -51840*a(n-15).

Example

Some solutions for n=7
..0..0..0..0..0..2..3....0..0..3..0..1..0..0....0..0..2..2..1..1..2
..2..0..0..0..3..1..1....0..0..0..0..0..2..0....0..0..1..3..1..1..3

Crossrefs

Cf. A231940.

Sequence in context: A159501 A172219 A172213 * A118675 A223962 A252834

Adjacent sequences: A231938 A231939 A231940 * A231942 A231943 A231944

Keyword

nonn

Author

R. H. Hardin, Nov 15 2013

Status

approved