A139523 Denominators of an Egyptian fraction for log(Pi), using only prime numbers and allowing repetitions.

2, 2, 7, 541, 41131, 627169013, 81471206061859301, 932806453618297780249534047168397, 4107347676766564181856839919490854246701477594547905851748592091

Offset

0,1

Comments

Good approximation up to 799 decimal digits

Links

Table of n, a(n) for n=0..8.

Maple

P:=proc(n) local a, i; a:=evalf(ln(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-A139522.

Sequence in context: A345759 A062448 A248237 * A359057 A137384 A051148

Adjacent sequences: A139520 A139521 A139522 * A139524 A139525 A139526

Keyword

easy,nonn,frac

Author

Paolo P. Lava and Giorgio Balzarotti, Apr 28 2008

Status

approved