A281534 Number of nX2 0..2 arrays with no element equal to more than one of its king-move neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

0, 0, 4, 104, 612, 3056, 16368, 82656, 397040, 1873344, 8687872, 39621504, 178384960, 794593024, 3506334976, 15347019264, 66696520448, 288032791552, 1236901206016, 5284853921792, 22477522539520, 95205886291968

Offset

1,3

Comments

Column 2 of A281540.

Links

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

Formula

Empirical: a(n) = 12*a(n-1) -54*a(n-2) +136*a(n-3) -324*a(n-4) +720*a(n-5) -1064*a(n-6) +1632*a(n-7) -2208*a(n-8) +2048*a(n-9) -1920*a(n-10) +1536*a(n-11) -512*a(n-12)

Example

Some solutions for n=4
..0..1. .0..1. .0..1. .0..1. .0..1. .0..1. .0..1. .0..1. .0..1. .0..1
..2..0. .0..2. .1..2. .0..1. .0..1. .0..2. .1..2. .0..2. .2..1. .0..1
..0..1. .2..0. .1..0. .2..0. .2..1. .0..2. .2..1. .2..0. .1..2. .0..1
..1..0. .2..1. .2..1. .0..2. .0..1. .0..1. .0..2. .1..0. .0..2. .2..2

Crossrefs

Cf. A281540.

Sequence in context: A102439 A331456 A211150 * A006415 A333434 A181396

Adjacent sequences: A281531 A281532 A281533 * A281535 A281536 A281537

Keyword

nonn

Author

R. H. Hardin, Jan 23 2017

Status

approved