A263595 Number of length n arrays of permutations of 0..n-1 with each element moved by -6 to 6 places and the median of every three consecutive elements nondecreasing.

1, 2, 6, 16, 52, 208, 800, 2900, 10960, 40792, 148288, 544600, 2000084, 7312332, 26795812, 98234356, 359845004, 1319030780, 4834945864, 17718152672, 64944710636, 238041386504, 872396576888, 3197533964256, 11719620057508

Offset

1,2

Comments

Column 6 of A263597.

Links

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

Formula

Empirical: a(n) = a(n-1) +a(n-2) +27*a(n-3) +11*a(n-4) +19*a(n-5) -17*a(n-6) +55*a(n-7) +207*a(n-8) +399*a(n-9) +842*a(n-10) +4810*a(n-11) +7064*a(n-12) -5048*a(n-13) -11662*a(n-14) +10885*a(n-15) -23133*a(n-16) -24495*a(n-17) +19889*a(n-18) -61624*a(n-19) -96905*a(n-20) -82792*a(n-21) -121206*a(n-22) -43903*a(n-23) -440813*a(n-24) -321679*a(n-25) +36248*a(n-26) -1481424*a(n-27) -184710*a(n-28) -147760*a(n-29) -954886*a(n-30) -1689620*a(n-31) +910782*a(n-32) -876748*a(n-33) -1449360*a(n-34) +1330892*a(n-35) +2445848*a(n-36) -1219064*a(n-37) +1399100*a(n-38) +2785232*a(n-39) +286256*a(n-40) +544140*a(n-41) +1489220*a(n-42) -40800*a(n-43) -524376*a(n-44) -119768*a(n-45) -395576*a(n-46) +110160*a(n-47) +418424*a(n-48) +649656*a(n-49) -332096*a(n-50) +215424*a(n-51) +84720*a(n-52) -2800*a(n-53) +293600*a(n-54) -3744*a(n-55) +128256*a(n-56) +40704*a(n-57) +10944*a(n-58) +11712*a(n-59) +2176*a(n-60) +9472*a(n-61) -1664*a(n-62) +3840*a(n-63) -2816*a(n-64) -256*a(n-65) -512*a(n-67)

Example

Some solutions for n=6
..2....4....1....1....5....0....0....4....1....0....2....0....1....1....0....1
..3....0....2....0....0....2....2....0....2....2....5....1....0....0....3....0
..0....1....0....2....1....3....1....1....5....4....0....3....2....5....1....3
..4....3....4....5....3....4....4....5....3....1....3....2....5....2....4....2
..5....2....5....4....2....1....5....3....0....3....4....4....3....3....5....4
..1....5....3....3....4....5....3....2....4....5....1....5....4....4....2....5

Crossrefs

Cf. A263597.

Sequence in context: A003446 A300668 A263594 * A263596 A263591 A218779

Adjacent sequences: A263592 A263593 A263594 * A263596 A263597 A263598

Keyword

nonn

Author

R. H. Hardin, Oct 22 2015

Status

approved