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A353163
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Expansion of e.g.f. exp(Sum_{p prime} x^p / (p-1)!).
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2
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1, 0, 2, 3, 12, 65, 210, 1477, 7560, 45864, 338310, 2176031, 17657640, 139280869, 1150004856, 10572694860, 94834041120, 931995595457, 9384294360168, 96974005210273, 1066116104926500, 11838081891521760, 137785102884102366, 1652584041236345933
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OFFSET
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0,3
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LINKS
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FORMULA
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a(0) = 1; a(n) = Sum_{p<=n, p prime} p * binomial(n-1,p-1) * a(n-p).
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PROG
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(PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(sum(k=1, N, isprime(k)*x^k/(k-1)!))))
(PARI) a(n) = if(n==0, 1, sum(k=1, n, isprime(k)*k*binomial(n-1, k-1)*a(n-k)));
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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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