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A324365
Number of permutations p of [n] having no index i with |p(i)-i| = 3.
3
1, 1, 2, 6, 14, 53, 265, 1554, 11024, 90816, 846032, 8803826, 101011765, 1265197857, 17167351014, 250725968406, 3920074915626, 65310957981693, 1154885557082749, 21599009876309400, 425919898969718528, 8831294211199266816, 192065262001816123136
OFFSET
0,3
LINKS
Wikipedia, Permutation
FORMULA
a(n) = n! - A324366(n).
EXAMPLE
a(4) = 14: 1234, 1243, 1324, 1342, 1423, 1432, 2134, 2143, 2314, 2413, 3124, 3142, 3214, 3412.
CROSSREFS
Column k=3 of A306512.
Sequence in context: A355093 A376075 A295974 * A346208 A354533 A192764
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Feb 23 2019
STATUS
approved