A264123 Number of (n+1) X (3+1) arrays of permutations of 0..n*4+3 with each element having index change +-(.,.) 0,0 1,-2 or 2,-1.

4, 45, 576, 5733, 53361, 533610, 5336100, 53361000, 533610000, 5336100000, 53361000000, 533610000000, 5336100000000, 53361000000000, 533610000000000, 5336100000000000, 53361000000000000, 533610000000000000

Offset

1,1

Links

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

Index entries for linear recurrences with constant coefficients, signature (10).

Formula

Empirical: a(n) = 10*a(n-1) for n>5.

Conjectures from Colin Barker, Jan 04 2019: (Start)

G.f.: x*(4 + 5*x + 126*x^2 - 27*x^3 - 3969*x^4) / (1 - 10*x).

a(n) = 53361*10^(n-5) for n>4.

(End)

Example

Some solutions for n=4:
..0..1..9..5....0..8..9..5....0..8..4.10....0..8..9..3....0..8..4..3
..4..3..8..7....4.12.13..7....2.12..6..7....4..5.13.14....2.12..6..9
..6..2.12.11....1..2..3.18....1.16..3.11....1..2.10.11....1..7.17.11
.10.13.16.15...10..6.14.17....5.13.14.17...12..6..7.17....5.13.14.15
.14.17.18.19...16.15.11.19....9.15.18.19...16.15.18.19...16.10.18.19

Crossrefs

Column 3 of A264128.

Sequence in context: A039657 A114473 A275125 * A304645 A233313 A377550

Adjacent sequences: A264120 A264121 A264122 * A264124 A264125 A264126

Keyword

nonn

Author

R. H. Hardin, Nov 03 2015

Status

approved