

A003756


Number of spanning trees with degrees 1 and 3 in S_4 X P_{2n1}.


0



1, 0, 24, 54, 492, 1944, 11976, 57024, 313440, 1587168, 8417472, 43483392, 227995008, 1185394176, 6192642048, 32263570944, 168350991360, 877689686016, 4578049517568, 23872537976832, 124504626978816, 649282059657216, 3386128302882816, 17658788068196352
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OFFSET

1,3


REFERENCES

F. Faase, On the number of specific spanning subgraphs of the graphs G X P_n, Ars Combin. 49 (1998), 129154.


LINKS

Table of n, a(n) for n=1..24.
F. Faase, On the number of specific spanning subgraphs of the graphs G X P_n, Preliminary version of paper that appeared in Ars Combin. 49 (1998), 129154.
F. Faase, Counting Hamiltonian cycles in product graphs
F. Faase, Results from the counting program
Index entries for sequences related to trees
Index entries for linear recurrences with constant coefficients, signature (2, 16, 4).


FORMULA

a(n) = 2*a(n1) + 16*a(n2) + 4*a(n3), n > 4.
G.f.: x*(1 + 8*x^2 + 2*x^3  2*x)/(1  2*x  16*x^2  4*x^3).  R. J. Mathar, Dec 16 2008


MATHEMATICA

Join[{1, 0}, LinearRecurrence[{2, 16, 4}, {24, 54, 492}, 20]] (* Harvey P. Dale, Mar 17 2013 *)


CROSSREFS

Sequence in context: A234238 A228876 A005782 * A135191 A216697 A316361
Adjacent sequences: A003753 A003754 A003755 * A003757 A003758 A003759


KEYWORD

nonn,easy


AUTHOR

Frans J. Faase; corrections Feb 07 2009


STATUS

approved



