A268626 Number of nX6 0..2 arrays with some element plus some horizontally or vertically adjacent neighbor totalling two no more than once.

336, 8586, 187224, 3819654, 74914554, 1430057208, 26758514760, 493042858032, 8974328440044, 161737670836314, 2891047134413940, 51321708535136676, 905714517532142694, 15902932976899644264, 277998507169027800234

Offset

1,1

Comments

Column 6 of A268628.

Links

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

Formula

Empirical: a(n) = 60*a(n-1) -1482*a(n-2) +20016*a(n-3) -167163*a(n-4) +924894*a(n-5) -3537110*a(n-6) +9593166*a(n-7) -18693789*a(n-8) +26218062*a(n-9) -26188161*a(n-10) +18139608*a(n-11) -8262712*a(n-12) +2220864*a(n-13) -266256*a(n-14) for n>15

Example

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

Crossrefs

Cf. A268628.

Sequence in context: A337875 A223446 A229697 * A258418 A268969 A056933

Adjacent sequences: A268623 A268624 A268625 * A268627 A268628 A268629

Keyword

nonn

Author

R. H. Hardin, Feb 09 2016

Status

approved