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A071840 Number of primes == 3 mod 8 <= n. 0

%I #5 Mar 30 2012 18:39:03

%S 0,0,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,

%T 3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,6,6,

%U 6,6,6,6,6,6,6,6,6,6,6,6,6,6,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7

%N Number of primes == 3 mod 8 <= n.

%o (PARI) for(n=1,200,print1(sum(i=1,n,if((i*isprime(i)-3)%8,0,1)),","))

%K easy,nonn

%O 1,11

%A _Benoit Cloitre_, Jun 08 2002

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)