A348195 Number of primes of the form 4k+3 < n^2.

0, 1, 2, 3, 5, 6, 8, 9, 12, 13, 15, 18, 21, 23, 26, 29, 32, 34, 37, 40, 43, 47, 52, 55, 59, 63, 67, 70, 75, 79, 83, 88, 93, 97, 101, 106, 111, 115, 123, 131, 136, 140, 146, 151, 157, 164, 169, 174, 181, 186, 193, 200, 207, 213, 221, 225, 230, 241, 246, 255, 263, 269, 280, 287, 294, 301, 308, 316, 326, 331, 343, 353, 358

Offset

1,3

Links

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

Formula

a(n) = A066490(n^2).

Prog

(PARI) a(n) = sum(k=2, n^2-1, isprime(k)&&k%4==3);

Crossrefs

Cf. A066490, A348193, A348196.

Sequence in context: A127936 A280771 A368363 * A280744 A331072 A096276

Adjacent sequences: A348192 A348193 A348194 * A348196 A348197 A348198

Keyword

nonn

Author

Seiichi Manyama, Oct 06 2021

Status

approved