A348196 Number of primes of the form 4k+1 < n^2.

0, 0, 1, 2, 3, 4, 6, 8, 9, 11, 14, 15, 17, 20, 21, 24, 28, 31, 34, 37, 41, 44, 46, 49, 54, 58, 61, 66, 70, 74, 78, 83, 87, 93, 98, 103, 107, 112, 116, 119, 126, 133, 136, 143, 148, 154, 159, 167, 175, 180, 184, 192, 201, 207, 212, 219, 226, 232, 240, 247, 255, 262, 268, 276, 283, 292, 300, 307, 314, 322, 331, 336, 346, 354

Offset

1,4

Links

Seiichi Manyama, Table of n, a(n) for n = 1..10000

Formula

a(n) = A066339(n^2).

Prog

(PARI) a(n) = sum(k=2, n^2-1, isprime(k)&&k%4==1);

Crossrefs

Cf. A066339, A348193, A348195.

Sequence in context: A135676 A102701 A255770 * A111208 A085500 A265414

Adjacent sequences: A348193 A348194 A348195 * A348197 A348198 A348199

Keyword

nonn

Author

Seiichi Manyama, Oct 06 2021

Status

approved