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A302435
Number of primes of the form b^2+3 for b <= 10^n.
3
5, 18, 110, 712, 5427, 44096, 373019, 3228862, 28494961
OFFSET
1,1
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
KEYWORD
nonn,more
AUTHOR
Seiichi Manyama, Apr 07 2018
STATUS
approved