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%I #4 Nov 20 2015 06:55:56
%S 0,9,22,112,716,3100,14871,73900,349328,1679736,8094842,38736132,
%T 186037049,893328303,4285139965,20570385615,98729249057,473793905479,
%U 2274044573512,10914002589581,52379748049810,251394035040131
%N Number of (n+1)X(4+1) arrays of permutations of 0..n*5+4 with each element having directed index change 1,1 2,2 -1,0 or 0,-1.
%C Column 4 of A264655.
%H R. H. Hardin, <a href="/A264651/b264651.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) +36*a(n-3) -18*a(n-4) +186*a(n-5) +83*a(n-6) +144*a(n-7) +684*a(n-8) -1872*a(n-9) +508*a(n-10) -5048*a(n-11) -3240*a(n-12) +720*a(n-13) -95040*a(n-14) +3072*a(n-15) +3456*a(n-16) +13824*a(n-18) for n>21
%e Some solutions for n=4
%e ..1..2..7..4..9....1..2..3..4..9....1..6..7..4..9....1..2..3..4..9
%e ..6..0.12.13..3...10..0..8.13.14...10.11..8..2..3...10.11..8.13.14
%e .15.16.17.14..8...15.16..6..7.19...15.12..0.14.19...15.16..0.18.19
%e .20.10..5.19.24...20.17..5.12.24...20.17..5.23.13...20.17..5..6..7
%e .21.22.23.11.18...21.22.23.11.18...21.22.16.24.18...21.22.23.24.12
%Y Cf. A264655.
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 20 2015
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