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A264021 Number of (6+1)X(n+1) arrays of permutations of 0..n*7+6 with each element having index change +-(.,.) 0,0 1,2 or 2,2.

%I A264021 #6 Nov 10 2015 10:53:51
%S A264021 1,233,54289,3524125,228765625,21860843125,2089022169025,
%T A264021 188902868291280,17081816640235776,1556476909654928976,
%U A264021 141824515583579002801,12912728820640619613016,1175668148128746582139456
%N A264021 Number of (6+1)X(n+1) arrays of permutations of 0..n*7+6 with each element having index change +-(.,.) 0,0 1,2 or 2,2.
%C A264021 Row 6 of A264017.
%H A264021 R. H. Hardin, <a href="/A264021/b264021.txt">Table of n, a(n) for n = 1..210</a>
%F A264021 Empirical: a(n) = 87*a(n-1) +32068*a(n-3) +180766*a(n-4) -3715198*a(n-5) -16639004*a(n-6) +149707392*a(n-7) +542256817*a(n-8) +224301365*a(n-9) +4280490864*a(n-10) -2613943512*a(n-11) +12541107972*a(n-12) -12056948868*a(n-13) +9621158616*a(n-14) -5946708960*a(n-15) -2779571151*a(n-16) +6286349025*a(n-17) -2468635920*a(n-18) -364811148*a(n-19) +148489470*a(n-20) -3874014*a(n-21) +2657124*a(n-22) +16767*a(n-24) +243*a(n-25) for n>31
%e A264021 Some solutions for n=3
%e A264021 ..6.11..2..3....6..7..2..3....6..7..2..3....0.11..2..3....0..1..2..3
%e A264021 ..4.15..0..7...14.11..0..1...10.11..0..1....4..5..6..7....4.11..6..7
%e A264021 ..8..9.10..1...18.15.10..5...18.15..4..5...18.15.10..1....8..9.10..5
%e A264021 .18.13.14..5...12.23..4..9...22.13.14..9...12.23.14..9...22.23.14.15
%e A264021 .16.17.12.19...26.17..8.19...16.27..8.19...26.17..8.19...26.17.18.19
%e A264021 .26.21.22.23...20.27.22.13...26.21.12.23...20.27.22.13...20.27.12.13
%e A264021 .24.25.20.27...24.25.16.21...24.25.20.17...24.25.16.21...24.25.16.21
%Y A264021 Cf. A264017.
%K A264021 nonn
%O A264021 1,2
%A A264021 _R. H. Hardin_, Nov 01 2015