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A167061
Number of spanning trees in G X P_n, where G = {{1, 2}, {1, 3}, {1, 4}, {1, 5}, {2, 3}, {2, 4}, {2, 5}, {3, 4}}.
1
40, 47040, 48384000, 49461807360, 50545351901000, 51651393970176000, 52781550346052950760, 53936428658183506928640, 55116575633234676605184000, 56322544581812152703647896000, 57554900528304912551898910864840, 58814220831251084699615165546496000, 60101095479875496770600392870888679560
OFFSET
1,1
REFERENCES
F. Faase, On the number of specific spanning subgraphs of the graphs A X P_n, Ars Combin. 49 (1998), 129-154.
FORMULA
a(n) = 1152 a(n-1)
- 138048 a(n-2)
+ 5263416 a(n-3)
- 72792384 a(n-4)
+ 279916416 a(n-5)
- 429599666 a(n-6)
+ 279916416 a(n-7)
- 72792384 a(n-8)
+ 5263416 a(n-9)
- 138048 a(n-10)
+ 1152 a(n-11)
- a(n-12)
G.f.: -40x(x^10 +24x^9 -7104x^8 +167016x^7 -378475x^6 +378475x^4 -167016x^3 +7104x^2 -24x -1)/ (x^12 -1152x^11 +138048x^10 -5263416x^9 +72792384x^8 -279916416x^7 +429599666x^6 -279916416x^5 +72792384x^4 -5263416x^3 +138048x^2 -1152x +1).
CROSSREFS
Sequence in context: A185194 A214138 A239168 * A283664 A159404 A323489
KEYWORD
nonn
AUTHOR
STATUS
approved