A040014 Number of primes < e^n.

0, 1, 4, 8, 16, 34, 79, 183, 429, 1019, 2466, 6048, 14912, 37128, 93117, 234855, 595341, 1516233, 3877186, 9950346, 25614562, 66124777, 171141897, 443963543, 1154106844, 3005936865, 7842921261, 20496470801, 53645077679, 140599114669, 368973074565, 969455391690, 2550043255883

Offset: 0

Author

Jud McCranie

Keywords

• nonn

Comments

a(n) = A000720(A000149(n)). - Reinhard Zumkeller, Mar 17 2015

Links

• David Baugh, Table of n, a(n) for n = 0..59 (terms n = 0..39 from Giovanni Resta, terms n = 40..59 found using Kim Walisch's primecount program).
• Index entries for sequences related to numbers of primes in various ranges

Crossrefs

Cf. A006880 and A007053.

Cf. A000720, A000149.

Programs

Haskell

a040014 = a000720 . a000149  -- Reinhard Zumkeller, Mar 17 2015

Mathematica

Table[PrimePi[Exp[n]], {n, 0, 33}]

Extensions

a(27)-a(29) from Robert G. Wilson v, Jun 09 2000

a(30)-a(32) from Seiichi Manyama, May 04 2016