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%I #4 Mar 20 2013 11:57:14
%S 160000,19683,455625,10546875,288507825,7939566675,223894186425,
%T 6318290752875,178826926010625,5061686863486275,143298073856716425,
%U 4056837300096090075,114852424247153593425,3251568434305627847475
%N Rolling icosahedron face footprints: number of 5Xn 0..19 arrays starting with 0 where 0..19 label faces of an icosahedron and every array movement to a horizontal or antidiagonal neighbor moves across an icosahedral edge
%C Row 5 of A223480
%H R. H. Hardin, <a href="/A223483/b223483.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 33*a(n-1) -86*a(n-2) -1564*a(n-3) +7040*a(n-4) -6480*a(n-5) -5088*a(n-6) +5824*a(n-7) -512*a(n-8) for n>13
%e Some solutions for n=3
%e ..0..5..0....0..5..0....0..5..0....0..5..0....0..5..7....0..5..0....0..5..7
%e ..7..5..7....0..1..4....9..5..0....0..2..0....0..5..7....0..5..0....7..6..7
%e ..9..5..9....4.17..4....0..2..8....0..2..8....7..5..9....0..5..7....7..5..9
%e ..9..8.13....4.17..4....3..2..8....8..2..3....7..5..0....7..6..1....7..5..7
%e ..2..8..2...18.17..4....8.13..8....0..2..3....0..1..0....1..0..2....7..6..1
%e Face neighbors:
%e 0 -> 1 2 5
%e 1 -> 0 4 6
%e 2 -> 0 3 8
%e 3 -> 2 4 16
%e 4 -> 3 1 17
%e 5 -> 0 7 9
%e 6 -> 1 7 10
%e 7 -> 6 5 11
%e 8 -> 2 9 13
%e 9 -> 8 5 14
%e 10 -> 6 12 17
%e 11 -> 7 12 14
%e 12 -> 11 10 19
%e 13 -> 8 15 16
%e 14 -> 9 11 15
%e 15 -> 14 13 19
%e 16 -> 3 13 18
%e 17 -> 4 10 18
%e 18 -> 16 17 19
%e 19 -> 15 18 12
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 20 2013
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