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A263690
Number of length n arrays of permutations of 0..n-1 with each element moved by -n to n places and every three consecutive elements having its maximum within 3 of its minimum.
3
1, 1, 2, 6, 24, 36, 36, 48, 80, 128, 200, 288, 432, 648, 992, 1496, 2272, 3424, 5192, 7840, 11880, 17952, 27184, 41096, 62208, 94072, 142368, 215328, 325832, 492864, 745736, 1128096, 1706800, 2582024, 3906464, 5909784, 8941024, 13526368, 20464072, 30959200
OFFSET
0,3
LINKS
FORMULA
Empirical: a(n) = a(n-1) +a(n-2) -a(n-3) +a(n-4) for n>12.
G.f.: (8*x^12+8*x^11-4*x^10-8*x^8+6*x^7+20*x^6-7*x^5-16*x^4-4*x^3-1) / (x^4-x^3+x^2+x-1). - Alois P. Heinz, Apr 08 2020
CROSSREFS
Diagonal of A263693.
Cf. A333833.
Sequence in context: A069141 A158977 A165823 * A137326 A163912 A257546
KEYWORD
nonn,easy
AUTHOR
R. H. Hardin, Oct 23 2015
EXTENSIONS
a(0), a(24)-a(39) from Alois P. Heinz, Apr 08 2020
STATUS
approved