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A294208
a(n) = reduced numerator of Sum_{p <= n} Sum_{k=1..floor(log(n)/log(p))} 1/p^k, where p runs over the primes.
1
0, 0, 1, 5, 13, 77, 77, 599, 1303, 4189, 4189, 48599, 48599, 659507, 659507, 659507, 1364059, 23909723, 23909723, 466536977, 466536977, 466536977, 466536977, 10963143031, 10963143031, 55886560931, 55886560931, 170634254393, 170634254393, 5028706810597
OFFSET
0,4
LINKS
FORMULA
a(n) = reduced numerator of Sum_{p <= n} (p^floor(log(n)/log(p)) - 1) / p^floor(log(n)/log(p)) / (p-1), where p runs over the primes.
PROG
(PARI) a(n) = numerator(sum(k=1, primepi(n), sum(j=1, logint(n, prime(k)), 1/prime(k)^j)))
(PARI) a(n) = numerator((sum(k=1, primepi(n), (prime(k)^logint(n, prime(k)) - 1) / prime(k)^logint(n, prime(k)) / (prime(k)-1))))
CROSSREFS
The corresponding denominator is A003418.
Sequence in context: A208821 A293259 A064169 * A081525 A027612 A027457
KEYWORD
nonn,frac
AUTHOR
Daniel Suteu, Oct 24 2017
STATUS
approved