login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A064646 Numerators of partial sums of reciprocals of primorial numbers. 1
1, 2, 7, 74, 543, 10589, 120009, 3420257, 4767631, 2281311434, 141441308909, 51307141467, 3301022547923, 200573000466191, 433638827007904943, 328326540448842314, 31534618884970203647, 13785884222546140694347 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..18.

EXAMPLE

n=5, Sum[1/q(j)],j=1..5 = 1/2+1/6+1/30+1/210+1/2310= (1155+385+77+11+1)/2310=1629/2310=543/770, a(5)=543

MATHEMATICA

q[x_] := Apply[Times, Table[Prime[j], {j, 1, x}]] a(n)=Numerator[Apply[Plus, Table[1/q[w], {w, 1, n}]]]

CROSSREFS

A002110.

Sequence in context: A119811 A319621 A167526 * A144905 A266880 A083455

Adjacent sequences:  A064643 A064644 A064645 * A064647 A064648 A064649

KEYWORD

frac,nonn

AUTHOR

Labos Elemer, Oct 04 2001

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 23 07:20 EDT 2018. Contains 316520 sequences. (Running on oeis4.)