A223507 Petersen graph (3,1) coloring a rectangular array: number of 4Xn 0..5 arrays where 0..5 label nodes of a graph with edges 0,1 0,3 3,5 3,4 1,2 1,4 4,5 2,0 2,5 and every array movement to a horizontal, diagonal or antidiagonal neighbor moves along an edge of this graph, with the array starting at 0.
216, 771, 20115, 426359, 9685063, 216562815, 4867038759, 109246101385, 2453094910375, 55078160026621, 1236680655855829, 27767207466078683, 623458974380912329, 13998557054872762899, 314310396038821269603
Offset: 1
Keywords
Examples
Some solutions for n=3 ..0..1..4....0..1..2....0..2..0....0..1..2....0..3..4....0..2..0....0..3..0 ..4..1..2....4..1..0....0..2..1....0..1..2....5..3..5....0..2..0....0..3..4 ..2..1..4....4..3..4....5..2..0....4..1..2....0..2..5....5..2..5....0..1..4 ..4..1..2....0..1..0....1..2..5....4..5..2....5..3..5....0..2..1....2..1..4
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Formula
Empirical: a(n) = 25*a(n-1) +a(n-2) -1509*a(n-3) +3743*a(n-4) +21956*a(n-5) -87188*a(n-6) -23069*a(n-7) +409623*a(n-8) -235845*a(n-9) -749323*a(n-10) +679813*a(n-11) +599294*a(n-12) -680632*a(n-13) -199246*a(n-14) +294548*a(n-15) +14686*a(n-16) -53558*a(n-17) +3396*a(n-18) +3220*a(n-19) -192*a(n-20) -64*a(n-21) for n>22
Comments