A302443 - OEIS

%I #17 Apr 15 2018 13:33:24

%S 3,19,119,849,6663,54514,460019,3982973,35174007

%N Number of primes of the form b^2-3 for b <= 10^n.

%e a(1) = 3 because there are 3 primes of the form b^2-3 for b <= 10 : 13, 61 and 97.

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

%Y Number of primes of the form b^2+m for b <= 10^n: this sequence (m=-3), A302442 (m=-2), A206709 (m=1), A302434 (m=2), A302435 (m=3).

%Y Cf. A028874.

%K nonn,more

%O 1,1

%A _Seiichi Manyama_, Apr 08 2018