A184023 1/8 the number of (n+1)X4 0..3 arrays with all 2X2 subblock sums the same

242, 491, 1052, 2597, 6650, 18701, 53948, 165929, 520322, 1709981, 5706212, 19735097, 69075290, 248513021, 902117708, 3343884089, 12473559602, 47261525021, 179833241972, 692191519097, 2671565177930, 10398142103741

Offset

1,1

Comments

Column 3 of A184029

Links

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

Formula

Empirical: a(n)=8*a(n-1)+16*a(n-2)-268*a(n-3)+189*a(n-4)+3388*a(n-5)-5824*a(n-6)-20048*a(n-7)+49756*a(n-8)+52752*a(n-9)-196896*a(n-10)-24192*a(n-11)+369216*a(n-12)-131328*a(n-13)-262656*a(n-14)+165888*a(n-15)

Example

Some solutions for 6X4
..2..1..2..1....1..2..1..2....1..1..1..1....1..3..1..2....1..1..3..2
..2..1..2..1....1..2..1..2....2..1..2..1....2..1..2..2....2..1..0..0
..0..3..0..3....2..1..2..1....1..1..1..1....1..3..1..2....1..1..3..2
..3..0..3..0....0..3..0..3....2..1..2..1....3..0..3..1....2..1..0..0
..2..1..2..1....2..1..2..1....1..1..1..1....1..3..1..2....0..2..2..3
..0..3..0..3....1..2..1..2....1..2..1..2....2..1..2..2....2..1..0..0

Crossrefs

Sequence in context: A039665 A259719 A023703 * A211406 A094908 A205594

Adjacent sequences: A184020 A184021 A184022 * A184024 A184025 A184026

Keyword

nonn

Author

R. H. Hardin Jan 08 2011

Status

approved