A033510 Number of matchings in graph P_{7} X P_{n}.

1, 21, 2356, 196785, 17525619, 1539222016, 135658637925, 11945257052321, 1052091957273408, 92657526436631289, 8160498611028648795, 718704019165239462736, 63297158846544276862187, 5574656798624151746571203, 490966794038702258639391536, 43240039834820302340627322251

Offset

0,2

Links

Andrew Howroyd, Table of n, a(n) for n = 0..200

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.

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

Sergey Perepechko, Generating function, May 07 2013

Sergey Perepechko, Text version of generating function

Crossrefs

Column 7 of triangle A210662.

Sequence in context: A215160 A250062 A219000 * A123844 A172622 A172675

Adjacent sequences: A033507 A033508 A033509 * A033511 A033512 A033513

Keyword

nonn

Author

Per H. Lundow

Extensions

Terms a(13) and beyond from Andrew Howroyd, Apr 18 2021

Status

approved