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A139395 Decimal expansion of the sum 1/p(1) + 1/(p(2)*p(3)) + 1/(p(4)*p(5)*p(6)) + ..., where p(n) is the n-th prime. 2
5, 6, 7, 6, 7, 0, 3, 1, 9, 8, 4, 4, 5, 1, 9, 7, 2, 0, 8, 4, 0, 6, 9, 8, 2, 4, 2, 2, 9, 4, 2, 3, 2, 6, 7, 2, 5, 5, 8, 1, 1, 4, 8, 1, 3, 7, 3, 4, 6, 7, 3, 7, 8, 6, 3, 8, 3, 4, 2, 4, 9, 4, 7, 0, 5, 4, 8, 5, 8, 5, 1, 8, 7, 8, 5, 8, 7, 8, 4, 5, 9, 7, 3, 8, 2, 4, 3, 4, 1, 1, 9, 8, 1, 2, 1, 4, 3, 8, 3, 7 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Absolute difference between this number and A139396 is about 0.002.

LINKS

Table of n, a(n) for n=0..99.

EXAMPLE

0.56767031984451972084069824229423267255811481373467378638342..

MAPLE

P:=proc(n) local a, b, i, j, k; a:=0.5; k:=1; for i from 2 by 1 to n do b:=1; for j from k by 1 to k+i-1 do b:=b*1/ithprime(j+1); od; k:=j; a:=evalf(a+b, 105); od; print(a); end: P(100);

CROSSREFS

Cf. A139396.

Sequence in context: A101288 A212479 A095942 * A029911 A205691 A002141

Adjacent sequences:  A139392 A139393 A139394 * A139396 A139397 A139398

KEYWORD

nonn,cons,easy

AUTHOR

Paolo P. Lava and Giorgio Balzarotti, Apr 18 2008

STATUS

approved

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Last modified May 22 06:32 EDT 2019. Contains 323478 sequences. (Running on oeis4.)