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A189439
Number of 7Xn array permutations with each element not moving, or moving one space N, SW or SE
1
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
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
KEYWORD
nonn
AUTHOR
R. H. Hardin Apr 22 2011
STATUS
approved