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A081215 a(n) = (n^(n+1)+(-1)^n)/(n+1)^2. 4
1, 0, 1, 5, 41, 434, 5713, 90075, 1657009, 34867844, 826446281, 21794641505, 633095889817, 20088655029078, 691413758034721, 25657845139503479, 1021273028302258913, 43404581642184336392, 1961870762757168078553 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Robert Israel, Table of n, a(n) for n = 0..387

FORMULA

a(n) = (-1)^n + Sum_{k=1..n} (-1)^(k+1)*(n+1)^(n-k)*C(n+1,n+2-k). - Gionata Neri, May 19 2016

E.g.f.: (Ei(1,x) - Ei(1,-LambertW(-x)))/x. - Robert Israel, May 19 2016

MAPLE

seq((j^(j+1)+(-1)^j)/(j+1)^2, j=0..50); # Robert Israel, May 19 2016

CROSSREFS

Sequence in context: A329123 A285064 A232685 * A218219 A140095 A259609

Adjacent sequences:  A081212 A081213 A081214 * A081216 A081217 A081218

KEYWORD

easy,nonn

AUTHOR

Vladeta Jovovic, Apr 17 2003

STATUS

approved

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Last modified April 3 00:35 EDT 2020. Contains 333195 sequences. (Running on oeis4.)