A189439 Number of 7Xn array permutations with each element not moving, or moving one space N, SW or SE

1, 85, 1245, 26589, 493941, 9557077, 181540773, 3467525301, 66045131269, 1258981901653, 23988387057381, 457127606313333, 8710469146675973, 165979359956189589, 3162723963901817637, 60265641669988070325

Offset

1,2

Comments

Row 7 of A189435

Links

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

Formula

Empirical: a(n) = 23*a(n-1) +26*a(n-2) -2256*a(n-3) +3272*a(n-4) +63936*a(n-5) -101752*a(n-6) -714624*a(n-7) +1041216*a(n-8) +3522752*a(n-9) -4444032*a(n-10) -7691264*a(n-11) +5545472*a(n-12) +11157504*a(n-13) -4947968*a(n-14) -4030464*a(n-15)

Example

Some solutions for 7X3
..0..1..2....3..1..2....3..1..2....0..1..2....0..1..2....3..4..2....0..1..2
..3..7..8....6..0..5....6..0..5....3..4..5....3..4..5....1..0..5....6..7..5
..6..5..4....9..7..4....4.10.11....6..7..8....6..7.11....6.10.11....4..3..8
..9.13.14...12..8.14....9..8..7...12.13.11...12..8.14....7..8.14....9.13.14
.12.11.10...15.11.10...12.13.17...10..9.14...15..9.10...12..9.17...12.11.10
.15.19.20...13.19.20...15.14.20...15.19.20...18.19.13...18.19.13...18.19.17
.18.17.16...18.17.16...18.19.16...18.17.16...16.17.20...16.15.20...16.15.20

Crossrefs

Sequence in context: A206163 A020239 A297587 * A166917 A206377 A351105

Adjacent sequences: A189436 A189437 A189438 * A189440 A189441 A189442

Keyword

nonn

Author

R. H. Hardin Apr 22 2011

Status

approved