login
A223446
4-level binary fanout graph coloring a rectangular array: number of nX5 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
1
336, 6432, 149120, 3364544, 78731136, 1806815040, 42196917280, 972415126144, 22683600827456, 523428338294528, 12204309920521600, 281744591491984896, 6568032234638862080, 151651626145836973056, 3535077529243329150464
OFFSET
1,1
COMMENTS
Column 5 of A223449
LINKS
FORMULA
Empirical: a(n) = 906*a(n-2) -242296*a(n-4) +26234128*a(n-6) -1334520192*a(n-8) +35594966912*a(n-10) -536458306048*a(n-12) +4806221908992*a(n-14) -26453346390016*a(n-16) +90451908067328*a(n-18) -189810835587072*a(n-20) +235660908953600*a(n-22) -163229455089664*a(n-24) +58818801172480*a(n-26) -9781116928000*a(n-28) +542373838848*a(n-30) -2415919104*a(n-32)
EXAMPLE
Some solutions for n=3
..4..8..4..1..0....0..1..4..1..0....2.10.14.10.14....7..4..8..4..7
..8..4..8..4..1....1..0..1..4..1....9..2.10..2.10....4..7..4..8..4
..4..7..4..1..0....0..2..0..1..4...11..9..2.10.13....7..4..7..4..8
CROSSREFS
Sequence in context: A184557 A337873 A337875 * A229697 A268626 A258418
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 20 2013
STATUS
approved