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A117694 a(n) = (n^n + n)/2. 3
1, 3, 15, 130, 1565, 23331, 411775, 8388612, 193710249, 5000000005, 142655835311, 4458050224134, 151437553296133, 5556003412779015, 218946945190429695, 9223372036854775816, 413620130943168382097, 19673204037648268787721 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
FORMULA
a(n) = (n^n + n)/2.
a(n) = A066068(n)/2, for n > 0.
E.g.f.: (1/2)*(x*exp(x) - LambertW(-x)/(1 + LambertW(-x))). - G. C. Greubel, Jul 23 2023
MATHEMATICA
Table[n^n+n, {n, 30}]/2
PROG
(Magma) [(n+n^n)/2: n in [1..30]]; // G. C. Greubel, Jul 23 2023
(SageMath) [(n+n^n)/2 for n in range(1, 31)] # G. C. Greubel, Jul 23 2023
CROSSREFS
Cf. A066068.
Sequence in context: A075475 A074241 A228365 * A264795 A222390 A281186
KEYWORD
nonn
AUTHOR
Alexander Adamchuk, Apr 12 2006
STATUS
approved

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Last modified May 25 06:40 EDT 2024. Contains 372782 sequences. (Running on oeis4.)