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Number of (4+1)X(n+1) arrays of permutations of 0..n*5+4 with each element having directed index change 0,1 2,2 1,0 -1,2 -2,-1 or -1,-1.
1

%I #4 Nov 12 2015 23:03:54

%S 1,85,529,7311,101862,1103666,13805196,169633649,2021225139,

%T 24679272503,299292066678,3620259337857,43944809107738,

%U 532640833103943,6455594272133455,78276807986884628,948887621876714100

%N Number of (4+1)X(n+1) arrays of permutations of 0..n*5+4 with each element having directed index change 0,1 2,2 1,0 -1,2 -2,-1 or -1,-1.

%C Row 4 of A264422.

%H R. H. Hardin, <a href="/A264425/b264425.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +66*a(n-2) +767*a(n-3) +1772*a(n-4) -5737*a(n-5) -60500*a(n-6) -147478*a(n-7) +248837*a(n-8) +915581*a(n-9) -595548*a(n-10) +1256272*a(n-11) +6424752*a(n-12) +2523024*a(n-13) +20229024*a(n-14) +12822912*a(n-15) -24975872*a(n-16) for n>18

%e Some solutions for n=4

%e ..6..0..1..9..3....6..7..8..2..3....6..7..1..9..3....6.12..1..9..7

%e .11..5.13..7..4...16.12.13.11..4....0.12.13.19..4....0..5..2..3..4

%e .16.17.23..8..2....5.17..0..1..9....5.17.18..8..2...16.17.11..8.13

%e .10.22.12.24.14...10.22.23.24.14...10.11.16.24.14...21.22.23.24.14

%e .15.20.21.18.19...15.20.21.18.19...15.20.21.22.23...15.20.10.18.19

%Y Cf. A264422.

%K nonn

%O 1,2

%A _R. H. Hardin_, Nov 12 2015