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A139515 Denominators of an Egyptian fraction for Pi^(-1), using only prime numbers. 2
5, 11, 37, 2677, 4634713, 2181903745507, 684230289204979551524201, 30504579964160123833007038252005864789931483751 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Good approximation up to 706 decimal digits.

LINKS

Table of n, a(n) for n=0..7.

MAPLE

P:=proc(n) local a, b, i, k; a:=evalf(Pi^(-1), 100); for i from 1 by 1 to n do if 1/ithprime(i)<a then a:=a-1/ithprime(i); print(a); print(ithprime(i)); fi; od; end: P(100000);

CROSSREFS

Cf. A139514, A139516-A139523.

Sequence in context: A074626 A090186 A205719 * A038708 A042719 A045717

Adjacent sequences:  A139512 A139513 A139514 * A139516 A139517 A139518

KEYWORD

easy,nonn,frac

AUTHOR

Paolo P. Lava and Giorgio Balzarotti, Apr 28 2008

EXTENSIONS

Next term has 179 digits.

STATUS

approved

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Last modified June 18 17:05 EDT 2019. Contains 324214 sequences. (Running on oeis4.)