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A189645
Number of n X 4 array permutations with each element moving zero or one space horizontally, diagonally or antidiagonally.
2
5, 185, 4277, 107080, 2631821, 64890337, 1598901325, 39401919001, 970964720320, 23927183356745, 589629702461885, 14530053018698289, 358059360274087325, 8823540150072892232, 217435624721745257829, 5358195248586080351465
OFFSET
1,1
COMMENTS
Column 4 of A189650.
LINKS
FORMULA
Empirical: a(n) = 30*a(n-1) -126*a(n-2) -298*a(n-3) +4076*a(n-4) -9643*a(n-5) -26*a(n-6) +67624*a(n-7) -249088*a(n-8) +187462*a(n-9) +574310*a(n-10) -970738*a(n-11) +67260*a(n-12) +489180*a(n-13) +209922*a(n-14) -640310*a(n-15) +258090*a(n-16) +58776*a(n-17) -37696*a(n-18) -25814*a(n-19) +20091*a(n-20) -3196*a(n-21) -638*a(n-22) +270*a(n-23) -30*a(n-24) +a(n-25).
EXAMPLE
Some solutions for 3 X 4:
..0..4..5..2....5..4..7..3....0..2..1..6....0..2..1..3....5..0..3..6
..1..6..3..7....1..0.11..2....5..4..3.10....9..5..7..6....1..4..7..2
..8.10..9.11....8..6..9.10....8..9..7.11....8..4.11.10....9..8.11.10
CROSSREFS
Sequence in context: A208403 A280797 A094081 * A228694 A268178 A208410
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 24 2011
STATUS
approved