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Number of matchings in graph C_{7} X P_{n}.
2

%I #13 May 25 2017 14:41:48

%S 1,29,3544,356863,37071837,3834744194,396924243197,41080815923665,

%T 4251834519798256,440060916969339903,45545908457817115829,

%U 4713960298263277400742,487890626842308225478637,50496238510861366500952793,5226315005423375187288746048

%N Number of matchings in graph C_{7} X P_{n}.

%D Per Hakan Lundow, Computation of matching polynomials and the number of 1-factors in polygraphs, Research reports, No 12, 1996, Department of Mathematics, Umea University.

%H Alois P. Heinz, <a href="/A033519/b033519.txt">Table of n, a(n) for n = 0..450</a>

%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^16 +5*x^15 -144*x^14 -917*x^13 +2525*x^12 +18314*x^11 -9907*x^10 -81619*x^9 +18056*x^8 +116675*x^7 -14719*x^6 -49054*x^5 -187*x^4 +4457*x^3 -20*x^2 -69*x +1) / (x^18 +6*x^17 -210*x^16 -1164*x^15 +10306*x^14 +54922*x^13 -76144*x^12 -470662*x^11 +132726*x^10 +1274736*x^9 +24246*x^8 -1032670*x^7 -58000*x^6 +244690*x^5 +158*x^4 -15844*x^3 +722*x^2 +98*x -1). - _Alois P. Heinz_, Dec 09 2013

%Y Row 7 of A287428.

%K nonn,easy

%O 0,2

%A _Per H. Lundow_