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A071839 Number of primes == 1 mod 8 <= n. 0

%I

%S 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,

%T 1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,

%U 2,2,2,2,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5

%N Number of primes == 1 mod 8 <= n.

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

%K easy,nonn

%O 1,41

%A _Benoit Cloitre_, Jun 08 2002

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Last modified October 14 00:26 EDT 2019. Contains 327991 sequences. (Running on oeis4.)