A223476 - OEIS

%I #5 Dec 18 2015 18:18:31

%S 1,27,2025,421875,288507825,622332801675,4468456626780825,

%T 104443823338086658275,8163685522687864520397825,

%U 2101858460730043160691131026875

%N Rolling icosahedron face footprints: number of n X n 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 Diagonal of A223480

%e Some solutions for n=3

%e ..0..1..0....0..2..8....0..2..8....0..2..8....0..2..8....0..2..8....0..2..8

%e ..0..5..7....8..9.14....0..2..3....0..2..8....0..2..0....3..2..8....8..2..3

%e ..7..5..9...14.11..7....3..4.17....8..2..8....3..2..0....3..2..3....3..4..3

%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 1,2

%A _R. H. Hardin_ Mar 20 2013