|
Search: id:A066274
|
|
|
| A066274 |
|
Number of endofunctions of [n] such that 1 is not a fixed point. |
|
+0
5
|
|
| 0, 2, 18, 192, 2500, 38880, 705894, 14680064, 344373768, 9000000000, 259374246010, 8173092077568, 279577021469772, 10318292052303872, 408700964355468750, 17293822569102704640, 778579070010669895696
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
LINKS
|
Milan Janjic, Enumerative Formulas for Some Functions on Finite Sets
|
|
FORMULA
|
a(n) = n^n - n^(n-1). E.g.f.: T^2/(1-T), where T=T(x) is Euler's tree function (see A000169)
|
|
EXAMPLE
|
a(2)=2: [1->2,2->1],[1->2,2->2]
|
|
MAPLE
|
with(finance):seq(futurevalue(n, n, n), n=0..16); # [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Mar 25 2009]
|
|
CROSSREFS
|
Cf. A045531, A066275
Sequence in context: A019581 A129627 A138413 this_sequence A052623 A116072 A092882
Adjacent sequences: A066271 A066272 A066273 this_sequence A066275 A066276 A066277
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Len Smiley (smiley(AT)math.uaa.alaska.edu), Dec 09 2001
|
|
|
Search completed in 0.002 seconds
|
