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%I #10 Jan 03 2019 15:13:23
%S 8,105,1573,20570,269225,3524125,46131250,603865625,7904703125,
%T 103473906250,1354491015625,17730517578125,232095488281250,
%U 3038169384765625,39770153564453125,520598068847656250
%N Number of (n+1) X (4+1) arrays of permutations of 0..n*5+4 with each element having index change +-(.,.) 0,0 1,2 or 2,2.
%H R. H. Hardin, <a href="/A264014/b264014.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 15*a(n-1) - 25*a(n-2) for n>4.
%F Empirical g.f.: x*(1 - 2*x)*(8 + x + 200*x^2) / (1 - 15*x + 25*x^2). - _Colin Barker_, Jan 03 2019
%e Some solutions for n=4:
%e .12.13..9..3..4....7..1..9..3..4....7.13.14..3..4....7.13..9..3..4
%e ..5..6.19..8..2....5.18..0..8..2...17.18.19..8..9...12.18..0..8..2
%e .10.18..0..1.14...10.11.24.13.14...10.11..0..1..2...17.23..5..1.14
%e .22.16.24.11..7...22.23.17..6.19...15.23..5..6.12...22.16.10..6.19
%e .20.21.15.23.17...20.21.15.16.12...20.21.22.16.24...20.21.15.11.24
%Y Column 4 of A264017.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 01 2015