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A235496
a(n) = round(n^n/n!).
2
1, 1, 2, 5, 11, 26, 65, 163, 416, 1068, 2756, 7148, 18614, 48639, 127463, 334865, 881658, 2325751, 6145597, 16263866, 43099804, 114356611, 303761260, 807692035, 2149632061, 5726042115, 15264691107, 40722913454, 108713644516, 290404350963, 776207020880
OFFSET
0,3
COMMENTS
We have two versions of this sequence, this and A240571, because there is no universal agreement on how to round a number like 9/2. - N. J. A. Sloane, Dec 13 2015
LINKS
FORMULA
a(n) = Round(A000312(n)/A000142(n)).
MAPLE
a:= n-> round(n^n/n!):
seq(a(n), n=0..32); # Alois P. Heinz, Dec 13 2015
MATHEMATICA
Table[Floor[n^n/n! + 1/2], {n, 40}]
PROG
(Magma) [Round(n^n/Factorial(n)): n in [1..40]];
(PARI) s=[]; for(n=1, 30, s=concat(s, round(n^n/n!))); s \\ Colin Barker, Jan 19 2014
CROSSREFS
See A240571 for another version.
Sequence in context: A182053 A306563 A308060 * A025245 A300125 A307576
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Jan 15 2014
STATUS
approved