A302435 Number of primes of the form b^2+3 for b <= 10^n.

5, 18, 110, 712, 5427, 44096, 373019, 3228862, 28494961

Offset

1,1

Links

Table of n, a(n) for n=1..9.

Example

a(1) = 5 because there are 5 primes of the form b^2+3 for b <= 10: 3, 7, 19, 67 and 103.

Prog

(PARI) {a(n) = sum(k=0, 10^n, isprime(k^2+3))}

Crossrefs

Number of primes of the form b^2+m for b <= 10^n: A302443 (m=-3), A302442 (m=-2), A206709 (m=1), A302434 (m=2), this sequence (m=3).

Cf. A049423.

Sequence in context: A158455 A009442 A332784 * A332467 A036688 A009348

Adjacent sequences: A302432 A302433 A302434 * A302436 A302437 A302438

Keyword

nonn,more

Author

Seiichi Manyama, Apr 07 2018

Status

approved