A187433 Number of (n+1)X2 0..2 arrays with no 2X2 subblock commuting with any of its horizontal and vertical 2X2 subblock neighbors

81, 646, 5344, 44195, 365485, 3022484, 24995294, 206705746, 1709412335, 14136474668, 116905624191, 966784526492, 7995101408646, 66117779901555, 546779908805283, 4521752985630622, 37393930782377369, 309239815576130829

Offset

1,1

Comments

Column 1 of A187441

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n)=a(n-1)+32*a(n-2)+160*a(n-3)+468*a(n-4)+929*a(n-5)+1244*a(n-6)+881*a(n-7)-471*a(n-8)-2281*a(n-9)-3120*a(n-10)-1743*a(n-11)+1386*a(n-12)+3903*a(n-13)+3547*a(n-14)+613*a(n-15)-2124*a(n-16)-2314*a(n-17)-511*a(n-18)+932*a(n-19)+840*a(n-20)+73*a(n-21)-281*a(n-22)-172*a(n-23)-25*a(n-24)+8*a(n-25)+2*a(n-26) for n>27

Example

Some solutions for 3X2
..0..2....2..2....1..1....1..2....1..0....0..1....1..1....2..1....0..2....2..2
..2..0....1..2....0..0....0..1....2..2....0..0....2..0....2..0....2..0....1..0
..2..2....1..2....0..1....2..1....1..0....0..1....2..2....2..1....1..0....2..1

Crossrefs

Sequence in context: A237629 A236720 A187441 * A269055 A236876 A185366

Adjacent sequences: A187430 A187431 A187432 * A187434 A187435 A187436

Keyword

nonn

Author

R. H. Hardin Mar 10 2011

Status

approved