A227022 Number of nX3 (0,1,2) arrays of permanents of 2X2 subblocks of some (n+1)X4 binary array with rows and columns of the latter in lexicographically nondecreasing order

12, 72, 335, 1366, 4948, 16115, 47659, 129463, 326522, 771653, 1722005, 3652726, 7406710, 14426468, 27103102, 49288384, 87029344, 149600861, 250930856, 411535151, 661105246, 1041922558, 1613307461, 2457351181, 3686223670

Offset

1,1

Comments

Column 3 of A227025

Links

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

Formula

Empirical: a(n) = (1/2217600)*n^11 + (1/48384)*n^10 + (19/241920)*n^9 + (199/2800)*n^7 - (4291/11520)*n^6 - (3567/1792)*n^5 + (1336261/24192)*n^4 - (95295341/302400)*n^3 + (851237/1440)*n^2 + (8658337/9240)*n - 3550 for n>6

Example

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

Crossrefs

Sequence in context: A118979 A014970 A236967 * A036392 A035472 A036398

Adjacent sequences: A227019 A227020 A227021 * A227023 A227024 A227025

Keyword

nonn

Author

R. H. Hardin Jun 27 2013

Status

approved