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A263746 Number of length n arrays of permutations of 0..n-1 with each element moved by -2 to 2 places and every three consecutive elements having its maximum within 5 of its minimum. 1
1, 2, 6, 14, 31, 73, 160, 357, 814, 1836, 4140, 9379, 21163, 47769, 107940, 243763, 550469, 1243468, 2808345, 6342601, 14325494, 32354798, 73074320, 165043749, 372759852, 841897006, 1901473298, 4294581633, 9699541870, 21906956858 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = a(n-1) + 2*a(n-2) + 2*a(n-3) - 3*a(n-5) + 7*a(n-6) - a(n-7) - 2*a(n-8) - 5*a(n-9) - 3*a(n-10) + 2*a(n-11) + 2*a(n-13).

Empirical g.f.: x*(1 + x + 2*x^2 + 2*x^3 + x^4 + 5*x^5 - 4*x^6 - 6*x^7 - 5*x^8 - 2*x^9 + 3*x^10 + x^11 + 2*x^12) / (1 - x - 2*x^2 - 2*x^3 + 3*x^5 - 7*x^6 + x^7 + 2*x^8 + 5*x^9 + 3*x^10 - 2*x^11 - 2*x^13). - Colin Barker, Jan 03 2019

EXAMPLE

Some solutions for n=10:

..0....0....0....1....1....0....1....1....0....2....0....0....2....1....0....0

..1....2....2....0....0....1....0....2....3....0....3....1....3....0....2....1

..3....1....3....3....2....3....3....0....1....4....1....2....0....3....1....4

..2....3....1....4....3....2....2....5....4....1....2....3....1....2....4....5

..6....4....5....2....4....4....5....4....2....5....6....5....4....6....3....2

..5....6....6....6....5....6....6....3....7....3....7....4....6....5....5....3

..4....5....4....7....6....8....4....8....6....8....4....7....5....4....6....6

..9....7....7....5....7....5....8....7....5....6....5....8....8....8....8....7

..7....9....9....9....8....9....7....6....9....9....8....6....7....7....9....8

..8....8....8....8....9....7....9....9....8....7....9....9....9....9....7....9

CROSSREFS

Column 2 of A263752.

Sequence in context: A263711 A263697 A291409 * A002524 A188493 A055292

Adjacent sequences:  A263743 A263744 A263745 * A263747 A263748 A263749

KEYWORD

nonn

AUTHOR

R. H. Hardin, Oct 25 2015

STATUS

approved

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Last modified November 13 00:25 EST 2019. Contains 329083 sequences. (Running on oeis4.)