A189451 Number of 3Xn array permutations with each element moving zero or one space horizontally or diagonally

1, 13, 80, 666, 5080, 40106, 313136, 2455013, 19221095, 150562121, 1179185280, 9235771513, 72336253737, 566554489205, 4437377818704, 34754532606346, 272205182385544, 2131971340412858, 16698071766102576, 130782997877002493

Offset

1,2

Comments

Row 3 of A189449

Links

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

Formula

Empirical: a(n) = 6*a(n-1) +26*a(n-2) -72*a(n-3) -195*a(n-4) +284*a(n-5) +555*a(n-6) -424*a(n-7) -555*a(n-8) +284*a(n-9) +195*a(n-10) -72*a(n-11) -26*a(n-12) +6*a(n-13) +a(n-14)

Example

Some solutions for 3X3
..1..0..2....0..2..1....0..1..2....0..2..1....0..1..2....1..0..2....0..5..2
..3..4..5....3..8..5....4..3..5....4..3..5....4..3..5....7..5..4....3..4..1
..7..6..8....6..7..4....6..8..7....6..8..7....7..6..8....6..3..8....6..8..7

Crossrefs

Sequence in context: A264381 A339851 A297678 * A133718 A241696 A052255

Adjacent sequences: A189448 A189449 A189450 * A189452 A189453 A189454

Keyword

nonn

Author

R. H. Hardin Apr 22 2011

Status

approved