OFFSET
1,2
REFERENCES
F. Faase, On the number of specific spanning subgraphs of the graphs G X P_n, Ars Combin. 49 (1998), 129-154.
LINKS
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, Results from the counting program
FORMULA
a(1) = 1,
a(2) = 10,
a(3) = 46,
a(4) = 238,
a(5) = 1170,
a(6) = 5882 and
a(n) = 5a(n-1) + 3a(n-2) - 19a(n-3) + 20a(n-4) - 4a(n-5).
G.f.: x(1+5x-7x^2-3x^3+12x^4-4x^5)/(1-5x-3x^2+19x^3-20x^4+4x^5). [From R. J. Mathar, Dec 16 2008]
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Added recurrence from Faase's web page. - N. J. A. Sloane, Feb 03 2009
STATUS
approved