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Number of perfect matchings in graph P_{13} X P_{2n}.
2

%I #12 Apr 13 2020 19:51:13

%S 1,377,413351,536948224,731164253833,1012747193318519,

%T 1412218550274852671,1974622635952709613247,2764079753958605286860951,

%U 3870940598132705729413670953,5422065916132126528319352874496,7595338059193606161156363370300487,10640045682768766172108553992086690201

%N Number of perfect matchings in graph P_{13} X P_{2n}.

%C In Karavaev and Perepechko generating functions G_m(x) for P_m X P_n graphs were found for all values of m up to 27.

%D A. M. Karavaev and S. N. Perepechko, Generating functions for dimer problem on rectangular lattices (in Russian), Information Processes, 13(2013), No4, 374-400.

%H Sergey Perepechko, <a href="/A241908/a241908.pdf">Generating function for A241908</a>

%o (PARI) {a(n) = sqrtint(polresultant(polchebyshev(2*n, 2, x/2), polchebyshev(13, 2, I*x/2)))} \\ _Seiichi Manyama_, Apr 13 2020

%Y Row 13 of array A099390.

%Y Cf. A028470, A028471, A028472, A028473, A028474, A187596.

%K nonn,easy

%O 0,2

%A _Sergey Perepechko_, May 01 2014