A055729 Number of primes <= 3^n.
0, 2, 4, 9, 22, 53, 129, 327, 847, 2227, 5968, 16097, 43934, 120739, 334349, 931260, 2607165, 7332159, 20700806, 58648288, 166677978, 475023803, 1357200840, 3886548158, 11152818693, 32064929886, 92349038518, 266398236486, 769616513836, 2226457080707, 6449247674296, 18703411700669, 54301968156067, 157820174545456
Offset: 0
Keywords
Links
- Robert Price, Table of n, a(n) for n = 0..51 (terms 0..49 from Henri Lifchitz)
- Index entries for sequences related to numbers of primes in various ranges
Programs
-
Mathematica
Table[PrimePi[3^n], {n, 0, 29}] -
PARI
a(n) = primepi(3^n); \\ Michel Marcus, Aug 25 2014
Formula
Extensions
a(28)-a(40) from Henri Lifchitz, Nov 11 2012