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A003756 Number of spanning trees with degrees 1 and 3 in S_4 X P_{2n-1}. 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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

REFERENCES

F. Faase, On the number of specific spanning subgraphs of the graphs G X P_n, Ars Combin. 49 (1998), 129-154.

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), 129-154.

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(n-1) + 16*a(n-2) + 4*a(n-3), 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

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Last modified December 11 07:35 EST 2019. Contains 329914 sequences. (Running on oeis4.)