cp's OEIS Frontend

A223276 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, diagonal or antidiagonal neighbor moves across an icosahedral edge.

%I A223276 #7 Jul 23 2025 03:57:04
%S A223276 1,15,849,72279,28271577,20570223999,72981761306721,
%T A223276 449769396657137031,15458246910651549408393,
%U A223276 798321445297149167278062831
%N A223276 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, diagonal or antidiagonal neighbor moves across an icosahedral edge.
%C A223276 Diagonal of A223282
%e A223276 Some solutions for n=3
%e A223276 ..0..2..3....0..5..0....0..2..8....0..1..4....0..2..3....0..2..0....0..5..9
%e A223276 ..0..2..8....9..5..7....0..2..8....4..1..6....3..2..0....3..2..3....0..5..7
%e A223276 ..3..2..0....9..5..9....3..2..0....6..1..6....3..2..0....8..2..8....0..5..7
%e A223276 Face neighbors:
%e A223276 0 -> 1 2 5
%e A223276 1 -> 0 4 6
%e A223276 2 -> 0 3 8
%e A223276 3 -> 2 4 16
%e A223276 4 -> 3 1 17
%e A223276 5 -> 0 7 9
%e A223276 6 -> 1 7 10
%e A223276 7 -> 6 5 11
%e A223276 8 -> 2 9 13
%e A223276 9 -> 8 5 14
%e A223276 10 -> 6 12 17
%e A223276 11 -> 7 12 14
%e A223276 12 -> 11 10 19
%e A223276 13 -> 8 15 16
%e A223276 14 -> 9 11 15
%e A223276 15 -> 14 13 19
%e A223276 16 -> 3 13 18
%e A223276 17 -> 4 10 18
%e A223276 18 -> 16 17 19
%e A223276 19 -> 15 18 12
%K A223276 nonn
%O A223276 1,2
%A A223276 _R. H. Hardin_ Mar 19 2013