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%I #12 Dec 13 2013 07:40:59
%S 1,4,50,444,4349,41348,396733,3795912,36350866,348013000,3332060177,
%T 31902067752,305441725601,2924400160544,27999196885618,
%U 268073721835248,2566628109851821,24573761479828684,235277465932911917,2252625667246251996,21567396521342873618
%N Number of perfect matchings in graph P_{2} X C_{3} X P_{n}.
%H Alois P. Heinz, <a href="/A028455/b028455.txt">Table of n, a(n) for n = 0..1000</a>
%H Per Hakan Lundow, <a href="http://www.theophys.kth.se/~phl/Text/1factors.pdf">Computation of matching polynomials and the number of 1-factors in polygraphs</a>, Research report, No 12, 1996, Department of Math., Umea University, Sweden.
%H Per Hakan Lundow, <a href="http://www.theophys.kth.se/~phl/Text/1factors2.ps.gz">Enumeration of matchings in polygraphs</a>, 1998.
%F G.f.: (x^6 +4*x^5 -4*x^4 -16*x^3 +4*x^2 +4*x -1) / (-x^8 -8*x^7 +22*x^6 +60*x^5 -67*x^4 -60*x^3 +22*x^2 +8*x -1). - _Alois P. Heinz_, Dec 09 2013
%K nonn
%O 0,2
%A _Per H. Lundow_