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A090472
Primes in A089897.
1
2, 5, 13, 103, 181, 3958349, 3745011198097903, 46240016923302054484370458782256657253421057237649913392609
OFFSET
1,1
COMMENTS
The logarithmic integral can be computed in PARI: Li(x) = -eint1(log(1/x)).
Next term is A089897(858), which has 256 digits.
In fact the prime terms are for n=2, 3, 5, 9, 10, 26, 57, 202, 858, 1508, 1552, 2285, 4244, (5000). - Robert G. Wilson v
MATHEMATICA
Select[ Floor[ LogIntegral[ 2^Range[202]]], PrimeQ[ # ] &] (* Robert G. Wilson v, Nov 09 2005 *)
PROG
(PARI) lip(n) = forstep(x=1, n, 1, y=floor(-eint1(log(1/2^x))); if(isprime(y), print1(y", ")))
CROSSREFS
Cf. A089897.
Sequence in context: A100843 A082101 A158712 * A120266 A230518 A241248
KEYWORD
nonn
AUTHOR
Cino Hilliard, Feb 01 2004
EXTENSIONS
Edited by David Wasserman, Nov 08 2005
STATUS
approved