A028479 Number of perfect matchings in graph C_{8} X P_{n}.

1, 2, 49, 392, 5041, 51842, 591361, 6422528, 71385601, 784792962, 8672638129, 95605150088, 1055154220849, 11638893993218, 128416422417409, 1416693454733312, 15629912636083201, 172434918695682818, 1902390033466290481, 20988007893796680072, 231549660454953439921

Offset

0,2

References

Per Hakan Lundow, "Computation of matching polynomials and the number of 1-factors in polygraphs", Research report, No 12, 1996, Department of Math., Umea University, Sweden.

Links

Alois P. Heinz, Table of n, a(n) for n = 0..900

Per Hakan Lundow, Enumeration of matchings in polygraphs, 1998.

Formula

G.f.: -(x^7-5*x^6 -21*x^5 +41*x^4 +41*x^3 -21*x^2 -5*x +1) / (x^9 -7*x^8 -56*x^7 +104*x^6 +280*x^5 -280*x^4 -104*x^3 +56*x^2 +7*x -1). - Alois P. Heinz, Dec 09 2013

Crossrefs

Sequence in context: A057563 A297819 A297989 * A189389 A001568 A221134

Adjacent sequences: A028476 A028477 A028478 * A028480 A028481 A028482

Keyword

nonn,easy

Author

Per H. Lundow

Status

approved