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%I #23 Apr 22 2022 05:31:49
%S 2,13,87,617,4807,39266,332384,2880937,25424820,227529387,2059036144,
%T 18803978497,173032844825,1602471005227,14922285950520
%N Number of primes of the form 3k+2 less than 10^n.
%C Computed by _T. D. Noe_, Dec 19 2003.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/ModularPrimeCountingFunction.html">Modular Prime Counting Function</a>.
%F a(n) = A091119(n) + 1.
%t p = Select[Table[3 i + 2, {i, 0, 10^7}], PrimeQ[#] &]; Table[Count[p, x_ /; x < 10^n], {n, 7}] (* _Robert Price_, May 29 2019 *)
%Y Cf. A003627, A091115, A091119.
%K nonn,more
%O 1,1
%A _Eric W. Weisstein_, Dec 19 2003
%E a(10) from _Robert G. Wilson v_, Dec 22 2003
%E a(11)-a(13) from _Chai Wah Wu_, Jul 01 2019
%E a(14)-a(15) added from the data at A091119 by _Amiram Eldar_, Apr 22 2022
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