A295347 Number of nX3 0..1 arrays with each 1 horizontally or vertically adjacent to 0, 2 or 3 1s.

5, 20, 76, 299, 1198, 4775, 19214, 77650, 314916, 1281050, 5224082, 21344769, 87348360, 357898094, 1467894633, 6025215866, 24746954977, 101691771957, 418041974157, 1719049438541, 7070709945652, 29088512708512, 119686780663978

Offset

1,1

Comments

Column 3 of A295352.

Links

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

Formula

Empirical: a(n) = 6*a(n-1) -4*a(n-2) -13*a(n-3) -8*a(n-4) -17*a(n-5) +35*a(n-6) -14*a(n-7) +43*a(n-8) +48*a(n-9) -41*a(n-10) +43*a(n-11) -25*a(n-12) -5*a(n-13) -18*a(n-14) -a(n-15) +2*a(n-16) +a(n-17) +a(n-18)

Example

Some solutions for n=5
..1..0..1. .1..1..0. .0..0..1. .0..1..0. .1..0..0. .0..1..1. .1..0..0
..0..0..0. .1..1..0. .0..0..0. .1..0..1. .0..0..0. .1..1..1. .0..0..0
..1..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .1..0..1. .0..0..0
..0..1..0. .1..1..0. .1..0..0. .0..0..0. .0..0..0. .1..1..1. .0..0..0
..0..0..1. .1..1..0. .0..0..1. .1..0..1. .1..0..1. .1..1..1. .0..1..0

Crossrefs

Cf. A295352.

Sequence in context: A057552 A300918 A269708 * A270985 A289786 A129869

Adjacent sequences: A295344 A295345 A295346 * A295348 A295349 A295350

Keyword

nonn

Author

R. H. Hardin, Nov 20 2017

Status

approved