A289494 Number of primes in the interval [3n, 4n].

1, 1, 1, 1, 2, 2, 1, 2, 2, 2, 3, 4, 3, 3, 3, 3, 4, 4, 5, 5, 5, 5, 5, 4, 4, 6, 6, 6, 7, 6, 6, 7, 7, 6, 7, 6, 5, 6, 6, 7, 8, 9, 8, 8, 9, 9, 8, 9, 10, 11, 10, 10, 10, 10, 9, 9, 10, 10, 11, 11, 11, 11, 12, 11, 11, 11, 10, 12, 12, 13, 14, 14, 14, 15, 14

Offset

1,5

Links

FUNG Cheok Yin, Table of n, a(n) for n = 1..10000

Andy Loo, On the Primes in the Interval [3n, 4n], arXiv:1110.2377 [math.NT], 2011.

Mathematica

Join[{1}, Rest[Table[PrimePi[4n]-PrimePi[3n], {n, 80}]]] (* Harvey P. Dale, Dec 30 2024 *)

Crossrefs

Cf. A035250, A289493, A289495, A289496, A289497, A289498, A289499, A289500.

Sequence in context: A029395 A029282 A333123 * A029286 A286221 A321347

Adjacent sequences: A289491 A289492 A289493 * A289495 A289496 A289497

Keyword

nonn,easy

Author

FUNG Cheok Yin, Jul 07 2017

Status

approved