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A072980 Numerator of b(n)=sum (k'<=n,1/k') where k' denotes the squarefree numbers. 1
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 (list; graph; refs; listen; history; internal format)
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.

CROSSREFS

Cf. A072983.

Sequence in context: A178709 A168378 A059200 * A128500 A043051 A024545

Adjacent sequences:  A072977 A072978 A072979 * A072981 A072982 A072983

KEYWORD

easy,frac,nonn

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Aug 21 2002

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Last modified February 15 16:56 EST 2012. Contains 205825 sequences.