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%I #4 Mar 18 2013 07:47:20
%S 243,9375,443451,22163655,1127761923,57728430255,2960941376139,
%T 151970441720919,7801619707803603,400536865551609279,
%U 20564155823714361819,1055802848340690163431,54207072655600127312547
%N Rolling icosahedron face footprints: number of nX6 0..19 arrays starting with 0 where 0..19 label faces of an icosahedron and every array movement to a horizontal or vertical neighbor moves across an icosahedral edge
%C Column 6 of A223209
%H R. H. Hardin, <a href="/A223207/b223207.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 77*a(n-1) -1444*a(n-2) +5860*a(n-3) +38744*a(n-4) -300016*a(n-5) +339296*a(n-6) +1286720*a(n-7) -2655360*a(n-8) -56832*a(n-9) +1682944*a(n-10) -149504*a(n-11) -163840*a(n-12)
%e Some solutions for n=3
%e ..0..2..0..1..6.10....0..1..6.10..6.10....0..5..0..2..3..4....0..5..9..5..9..8
%e ..5..0..1..0..1..6....5..0..1..6..1..6....5..0..2..3.16..3....5..9..5..9..8..9
%e ..0..2..0..1..6.10....0..1..4..1..6..1....0..2..3..2..3.16....0..5..0..5..9.14
%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 18 2013
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