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Number of primes of the form 4k+3 < n^2.
3

%I #13 Oct 07 2021 07:22:58

%S 0,1,2,3,5,6,8,9,12,13,15,18,21,23,26,29,32,34,37,40,43,47,52,55,59,

%T 63,67,70,75,79,83,88,93,97,101,106,111,115,123,131,136,140,146,151,

%U 157,164,169,174,181,186,193,200,207,213,221,225,230,241,246,255,263,269,280,287,294,301,308,316,326,331,343,353,358

%N Number of primes of the form 4k+3 < n^2.

%H Seiichi Manyama, <a href="/A348195/b348195.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A066490(n^2).

%o (PARI) a(n) = sum(k=2, n^2-1, isprime(k)&&k%4==3);

%Y Cf. A066490, A348193, A348196.

%K nonn

%O 1,3

%A _Seiichi Manyama_, Oct 06 2021