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A141151
L.g.f.: A(x) = log( Sum_{n>=0} n^n*x^n ) = Sum_{n>=1} a(n)*x^n/n.
3
1, 7, 70, 899, 14001, 255532, 5342541, 125876003, 3300437302, 95338188007, 3009043615073, 103043811158864, 3805827820399125, 150819894172935183, 6383815674758486310, 287459477551898694403, 13721584934214631377921
OFFSET
1,2
LINKS
FORMULA
a(n) ~ n^(n+1). - Vaclav Kotesovec, May 30 2019
EXAMPLE
L.g.f.: A(x) = x + 7*x^2/2 + 70*x^3/3 + 899*x^4/4 + 14001*x^5/5 + ...
exp(A(x)) = 1 + x + 4*x^2 + 27*x^3 + 256*x^4 + 3125*x^5 + 46656*x^6 + ...
MATHEMATICA
With[{m=20}, Drop[CoefficientList[Series[Log[Sum[If[n==0, 1, n^n*x^n], {n, 0, m+2}]], {x, 0, m}], x], 1]*Range[1, m]] (* G. C. Greubel, May 30 2019 *)
PROG
(PARI) {a(n)=polcoeff(x*deriv(log(Ser(concat(1, vector(n+1, k, k^k))))), n)}
(Magma) m:=20; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!( Log( (&+[n^n*x^n: n in [0..m+2]]) ) )); [n*b[n]: n in [1..m-1]]; // G. C. Greubel, May 30 2019
(Sage) m = 20; T = taylor(log( sum(n^n*x^n for n in (0..m+2)) ), x, 0, m); [n*T.coefficient(x, n) for n in (1..m)] # G. C. Greubel, May 30 2019
CROSSREFS
Sequence in context: A226805 A113343 A124566 * A001669 A051604 A346668
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Jun 11 2008
STATUS
approved