A264581 Number of (n+1)X(6+1) arrays of permutations of 0..n*7+6 with each element having directed index change 1,0 0,-1 1,2 or -1,1.

1, 56, 333, 2232, 30718, 314166, 2561017, 24729380, 248623843, 2294091610, 21321186497, 204951390856, 1942216548168, 18230545326138, 172631845704811, 1636624660988864, 15453906528343116, 146032030188390140

Offset

1,2

Comments

Column 6 of A264583.

Links

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

Formula

Empirical: a(n) = 38*a(n-2) +592*a(n-3) +1657*a(n-4) -9886*a(n-5) -136311*a(n-6) -387548*a(n-7) +1158155*a(n-8) +15681368*a(n-9) +33962016*a(n-10) -85970624*a(n-11) -1017389376*a(n-12) -1493591040*a(n-13) +4158301440*a(n-14) +42008353792*a(n-15) +35065790464*a(n-16) -129986838528*a(n-17) -1159841185792*a(n-18) -356446240768*a(n-19) +2419915227136*a(n-20) +22114925019136*a(n-21) -1032478261248*a(n-22) -21988705828864*a(n-23) -292298730504192*a(n-24) +49701562875904*a(n-25) -2783944114176*a(n-26) +2605298170724352*a(n-27) -254077380329472*a(n-28) +1794884012867584*a(n-29) -14810971381956608*a(n-30) -943655854538752*a(n-31) -13405245765844992*a(n-32) +48976645947654144*a(n-33) +7036874417766400*a(n-34) +31525197391593472*a(n-35) -72057594037927936*a(n-36) for n>40

Example

Some solutions for n=4
..1..2..3..4.10..6.12....1..2..3..9..5.11.12....1..7..3..4..5..6.12
..8.14..0.16.17..5.19....8.14..0.16..4.13..6....0..9.10.16..2.13.19
..7.21..9.23.11.20.13...15.21..7.18.19.10.26...15..8.22.18.11.25.26
.22.28.24.15.26.27.18...22.28.24.17.31.27.20...14.28.29.17.31.32.20
.29.30.31.32.33.34.25...29.30.23.32.33.34.25...21.30.23.24.33.34.27

Crossrefs

Cf. A264583.

Sequence in context: A253922 A220015 A005912 * A220202 A104677 A156375

Adjacent sequences: A264578 A264579 A264580 * A264582 A264583 A264584

Keyword

nonn

Author

R. H. Hardin, Nov 18 2015

Status

approved