

A072980


Numerator of b(n)=sum (k'<=n,1/k') where k' denotes the squarefree numbers.


2



1, 3, 11, 11, 61, 11, 82, 82, 82, 171, 1951, 1951, 26133, 13424, 41273, 41273, 716656, 716656, 13871719, 13871719, 4700888, 9548741, 222854273, 222854273, 222854273, 112857219, 112857219, 112857219, 3310041496, 20075905417
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OFFSET

1,2


COMMENTS

b(n) was used by Niven in the 70's for an alternative proof of the divergence of the sum of reciprocal of primes.


LINKS



PROG

(PARI) a(n) = numerator(sum(k=1, n, issquarefree(k)/k)); \\ Michel Marcus, Nov 28 2013


CROSSREFS



KEYWORD

easy,frac,nonn


AUTHOR



STATUS

approved



