A223445 4-level binary fanout graph coloring a rectangular array: number of nX4 0..14 arrays where 0..14 label nodes of a graph with edges 0,1 1,3 3,5 3,6 1,4 4,7 4,8 0,2 2,9 9,11 9,12 2,10 10,13 10,14 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph

144, 1616, 20640, 262368, 3364544, 43139520, 553773760, 7110140800, 91312361088, 1172796624128, 15064174682368, 193501020879360, 2485596168674816, 31928841920689152, 410146384220210176, 5268614337966065664

Offset

1,1

Comments

Column 4 of A223449

Links

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

Formula

Empirical: a(n) = 24*a(n-1) -154*a(n-2) -56*a(n-3) +2992*a(n-4) -6256*a(n-5) -4320*a(n-6) +19040*a(n-7) -6016*a(n-8) -12928*a(n-9) +9600*a(n-10) -1792*a(n-11) for n>12

Example

Some solutions for n=3
.10..2.10..2....3..5..3..1...10..2..0..2...14.10..2..9...13.10..2.10
.13.10..2.10....5..3..1..0...13.10..2.10...10.14.10..2...10.13.10.13
.10..2..9..2....3..1..3..1...10..2.10..2...13.10.14.10...14.10..2.10

Crossrefs

Sequence in context: A109117 A209205 A223594 * A186934 A356731 A368508

Adjacent sequences: A223442 A223443 A223444 * A223446 A223447 A223448

Keyword

nonn

Author

R. H. Hardin Mar 20 2013

Status

approved