A264424 Number of (3+1) X (n+1) arrays of permutations of 0..n*4+3 with each element having directed index change 0,1 2,2 1,0 -1,2 -2,-1 or -1,-1.

1, 20, 96, 499, 2681, 15088, 86469, 479787, 2666733, 14940857, 83531649, 466766772, 2608467230, 14576309209, 81469725947, 455319456892, 2544569549821, 14220929241086, 79476850018075, 444172492025104, 2482352553030166

Offset

1,2

Comments

Row 3 of A264422.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +a(n-2) +50*a(n-3) -47*a(n-4) +214*a(n-5) -752*a(n-6) -111*a(n-7) -426*a(n-8) +2579*a(n-9) +1278*a(n-10) -4700*a(n-11) +19726*a(n-12) -3406*a(n-13) -3587*a(n-14) -55733*a(n-15) -17896*a(n-16) -7934*a(n-17) -4722*a(n-18) -5228*a(n-19) +15420*a(n-20) +47468*a(n-21) +9368*a(n-22) +6264*a(n-23) +6632*a(n-24) +6960*a(n-25) -4912*a(n-26) -13680*a(n-27) +1056*a(n-28) -1184*a(n-29) -1440*a(n-30) -128*a(n-32) +384*a(n-33).

Example

Some solutions for n=4
.11..0..8..2..3....6..0..8..2..3....6..0..1..9..3...11..7..1..9..3
.16..1.13.14..4...11.12.18.19..4...11.12.18.19..4....0.12.13.19..4
..5.17..7.19..9...16.17..7..1..9....5.17..7..8..2....5.17.18..8..2
.10.15.12..6.18...10.15..5.13.14...10.15.16.13.14...10.15.16..6.14

Crossrefs

Cf. A264422.

Sequence in context: A221704 A222772 A267646 * A039610 A177498 A157429

Adjacent sequences: A264421 A264422 A264423 * A264425 A264426 A264427

Keyword

nonn

Author

R. H. Hardin, Nov 12 2015

Status

approved