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A264239 Number of (n+1) X (3+1) arrays of permutations of 0..n*4+3 with each element having directed index change 0,0 1,1 0,-1 -1,1 or 0,-2. 1

%I

%S 21,95,804,5055,36193,243881,1688581,11546272,79399773,544596821,

%T 3739740969,25667019555,176203806580,1209502867667,8302721830885,

%U 56993334702205,391230050623617,2685581075271584,18435090548352201

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

%H R. H. Hardin, <a href="/A264239/b264239.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 7*a(n-1) + 7*a(n-2) - 65*a(n-3) + 65*a(n-4) + 62*a(n-5) - 72*a(n-6).

%F Empirical g.f.: x*(1 + x)*(21 - 73*x + 65*x^2 + 62*x^3 - 72*x^4) / (1 - 7*x - 7*x^2 + 65*x^3 - 65*x^4 - 62*x^5 + 72*x^6). - _Colin Barker_, Jan 06 2019

%e Some solutions for n=4:

%e ..1..2..5..3....0..1..5..3....0..4..2..3....1..4..3..6....1..4..2..3

%e ..4..0..6..7....4..8..7..2....6..8..1..7....5..0..7..2....5..0..6..7

%e ..9.11.13.14...10.12.11..6...10.12..5.11....8..9.13.11....8..9.13.11

%e .12..8.15.10...13.14..9.15...14.16..9.15...12.14.15.10...14.15.17.10

%e .16.17.18.19...16.17.18.19...18.17.13.19...16.17.18.19...16.12.18.19

%Y Column 3 of A264244.

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 09 2015

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Last modified September 16 17:39 EDT 2021. Contains 347473 sequences. (Running on oeis4.)