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A120264 Numerator of Sum[ (-1)^(k+1)/k^k, {k,1,n} ]. 0
1, 3, 85, 5413, 16922537, 456895999, 376274084904457, 24659496552164597077, 13105067550356276873597957, 40953336089635928267832533257, 11684464736880059106484670339210887010027 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Denominator of Sum[1/k^k*(-1)^(k+1),{k,1,n}] is A061464(n).

Sum[ (-1)^(k+1) / k^k, {k,1,Infinity} ] = Integrate[ x^x, {x,0,1} ] = 0.7834305107154659... A083648(n) gives its decimal expansion {7, 8, 3, 4, 3, 0, 5, 1, 0, 7, 1, 2, 1, 3, 4, 4, 0, 7, 0, 5, 9, ...}. - Alexander Adamchuk, Aug 21 2006

LINKS

Table of n, a(n) for n=1..11.

Eric Weisstein's World of Mathematics, Sophomore's Dream.

FORMULA

a(n) = numerator[[Sum[1/k^k*(-1)^(k+1),{k,1,n}]].

MATHEMATICA

Numerator[Table[Sum[1/k^k*(-1)^(k+1), {k, 1, n}], {n, 1, 20}]]

CROSSREFS

Cf. A061463, A061464.

Cf. A083648.

Sequence in context: A056262 A042587 A156879 * A292830 A185142 A279020

Adjacent sequences:  A120261 A120262 A120263 * A120265 A120266 A120267

KEYWORD

frac,nonn

AUTHOR

Alexander Adamchuk, Jun 30 2006

STATUS

approved

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Last modified July 30 17:21 EDT 2021. Contains 346359 sequences. (Running on oeis4.)