A223300 4X4X4 triangular graph coloring a rectangular array: number of nX3 0..9 arrays where 0..9 label nodes of a graph with edges 0,1 0,2 1,2 1,3 1,4 2,4 3,4 2,5 4,5 3,6 3,7 4,7 6,7 4,8 5,8 7,8 5,9 8,9 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph

144, 3132, 76788, 1882500, 46589268, 1148040516, 28402185108, 700525554180, 17321067229140, 427424478219972, 10564355081565972, 260773436696057988, 6443737539288281940, 159091220790299549508, 3930517719610405689492

Offset

1,1

Comments

Column 3 of A223305

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 10*a(n-1) +500*a(n-2) -2878*a(n-3) -15863*a(n-4) +79004*a(n-5) +144196*a(n-6) -616760*a(n-7) -363504*a(n-8) +1348864*a(n-9) +396544*a(n-10) -600576*a(n-11) for n>12

Example

Some solutions for n=3
..2..1..4....7..4..1....7..4..2....1..2..1....9..8..5....9..8..4....5..4..3
..4..3..7....4..1..4....6..3..1....2..1..0....5..9..8....8..4..8....4..3..4
..7..4..3....1..4..8....7..4..2....1..2..1....9..5..9....9..8..7....8..4..7

Crossrefs

Sequence in context: A221695 A223323 A251433 * A330837 A252182 A187166

Adjacent sequences: A223297 A223298 A223299 * A223301 A223302 A223303

Keyword

nonn

Author

R. H. Hardin Mar 19 2013

Status

approved