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A263662
Number of length n arrays of permutations of 0..n-1 with each element moved by -4 to 4 places and with no two consecutive increases or two consecutive decreases.
1
1, 2, 4, 10, 32, 95, 208, 486, 1064, 2560, 6000, 14636, 33680, 81608, 187488, 454456, 1046368, 2537664, 5840768, 14162704, 32593088, 79031008, 181889408, 441050016, 1015068544, 2461353728, 5664729088, 13735909824, 31612832000, 76655260288
OFFSET
1,2
COMMENTS
Column 4 of A263666.
LINKS
FORMULA
Empirical: a(n) = 4*a(n-2) +6*a(n-4) +16*a(n-6) -8*a(n-10) for n>20
EXAMPLE
Some solutions for n=7
..1....1....4....0....0....1....0....3....3....2....2....1....1....1....0....2
..5....4....1....5....3....2....4....1....2....1....0....0....0....3....4....0
..0....2....5....1....2....0....2....4....5....5....6....5....4....2....3....3
..4....3....0....6....6....5....5....0....0....0....1....2....3....5....5....1
..2....0....3....3....1....3....1....5....4....6....5....4....5....0....1....6
..6....6....2....4....5....6....6....2....1....3....3....3....2....6....6....4
..3....5....6....2....4....4....3....6....6....4....4....6....6....4....2....5
CROSSREFS
Cf. A263666.
Sequence in context: A005269 A070900 A296003 * A151400 A363138 A367113
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 23 2015
STATUS
approved