OFFSET
1,1
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
Faase gives a 12-term linear recurrence on his web page:
a(1) = 5,
a(2) = 130,
a(3) = 1660,
a(4) = 16820,
a(5) = 152230,
a(6) = 1275680,
a(7) = 10154290,
a(8) = 77897010,
a(9) = 581452680,
a(10) = 4250594690,
a(11) = 30572999140,
a(12) = 217099260110,
a(13) = 1525905283670,
a(14) = 10636695448300 and
a(n) = 19a(n-1) - 127a(n-2) + 328a(n-3) - 117a(n-4) - 675a(n-5)
+ 1127a(n-6) - 1016a(n-7) + 380a(n-8) + 12a(n-9) - 140a(n-10)
+ 68a(n-11) - 20a(n-12), n>14.
G.f. 5*x+130*x^2 -10*x^3*(-166 +1472*x -4347*x^2 +2503*x^3 +7316*x^4 -13386*x^5 +12513*x^6 -4715*x^7 -215*x^8 +1824*x^9 -856*x^10 +252*x^11) / ( (1-7*x-x^2+20*x^3-3*x^4+3*x^5+5*x^6) *(-1+6*x-4*x^2+2*x^3)^2 ). - R. J. Mathar, Aug 21 2012
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Added recurrence from Faase's web page. - N. J. A. Sloane, Feb 03 2009
STATUS
approved