OFFSET
1,1
LINKS
FORMULA
If b(n) denotes the number of spanning trees with degrees 1 and 3 in P_5 X P_n we have:
b(1) = 0,
b(2) = 1320,
b(3) = 0,
b(4) = 8872800,
b(5) = 0,
b(6) = 57159820320,
b(7) = 0,
b(8) = 368270723329920,
b(9) = 0,
b(10) = 2372720981421121920,
b(11) = 0,
b(12) = 15287133546258050856960,
b(13) = 0,
b(14) = 98493019073706019959014400, and
b(n) = 6288b(n-2) + 990168b(n-4) + 49284576b(n-6) - 334385280b(n-8) - 782880768b(n-10) - 34504704b(n-12).
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Ralf Stephan, Mar 28 2004
EXTENSIONS
Added recurrence from Faase's web page. - N. J. A. Sloane, Feb 03 2009
STATUS
approved