A277063 Number of primes <= n-th Bell number.

0, 0, 1, 3, 6, 15, 46, 151, 570, 2376, 10961, 54941, 297220, 1720725, 10602541, 69176095, 475881437, 3439093081, 26026621617, 205694058211, 1693554793730, 14494778231067, 128711956613875, 1183763037547762, 11258075170582653, 110558809039675629, 1119649516271861536

Offset: 0

Author

Vincenzo Librandi, Nov 10 2016

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 0..28 (calculated using Kim Walisch's primecount)
• Kim Walisch, Fast C++ prime counting function implementation (primecount).

Crossrefs

Cf. A000110, A000720, A054782, A277062.

Programs

Magma

[#PrimesUpTo(Bell(n)): n in [0..14]];

Mathematica

Table[PrimePi[BellB[n]], {n, 0, 20}]

Formula

a(n) = A000720(A000110(n)). - Michel Marcus, Nov 10 2016

Extensions

a(21)-a(26) from Charles R Greathouse IV, Nov 10 2016