A264521 Number of (3+1)X(n+1) arrays of permutations of 0..n*4+3 with each element having directed index change -1,0 0,2 -1,-2 or 1,0.

1, 3, 9, 42, 196, 644, 2116, 6854, 22201, 78076, 274576, 937960, 3204100, 10890360, 37015056, 126620208, 433139344, 1480295124, 5059050129, 17273618712, 58979036736, 201463380504, 688168134481, 2350844113032, 8030694487104

Offset: 1

Author

R. H. Hardin, Nov 16 2015

Keywords

• nonn

Comments

Row 3 of A264520.

Examples

			Some solutions for n=4
..5..6..9..1..2....7..6..0..1..2....7..8..0..1..9....5..6..7..1..2
..0.13.14..3..4...12.13.14..3..4...12.13..2..3..4....0.13.12..3..4
.15.18..7..8.19....5.18.19..8..9....5..6.17.18.19...17.18.19..8..9
.10.11.12.16.17...10.11.15.16.17...10.11.15.16.14...10.11.15.16.14
		

Links

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

Crossrefs

Cf. A264520.