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A179114
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G.f.: A(x) = exp( Sum_{n>=1} A179115(n)*x^n/n ), where A179115(n) = Sum_{d|n} phi(d^tau(d)).
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1
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1, 1, 2, 4, 13, 19, 103, 131, 515, 777, 2183, 3387, 92950, 98220, 215084, 407878, 1321714, 1941644, 10099460, 13008998, 49257496, 74663830, 209907775, 326405877, 5955260642, 6463849558, 14769440215, 27326857279, 88012522809
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OFFSET
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0,3
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COMMENTS
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phi(n) = A000010(n) is the Euler totient function of n.
tau(n) = A000005(n) is the number of divisors of n.
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LINKS
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EXAMPLE
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G.f.: A(x) = 1 + x + 2*x^2 + 4*x^3 + 13*x^4 + 19*x^5 + 103*x^6 +...
log(A(x)) = x + 3*x^2/2 + 7*x^3/3 + 35*x^4/4 + 21*x^5/5 + 441*x^6/6 +...
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PROG
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(PARI) {a(n)=polcoeff(exp(sum(m=1, n, sumdiv(m, d, eulerphi(d^sigma(d, 0)))*x^m/m)+x*O(x^n)), n)}
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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