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A091129 Number of primes of the form 8k+7 less than 10^n. 4

%I

%S 1,6,43,308,2399,19669,166237,1440406,12711702,113766208,1029523130,

%T 9401993203,86516416092,801235499451

%N Number of primes of the form 8k+7 less than 10^n.

%C Computed by _T. D. Noe_, Dec 19 2003.

%H Bernhard Helmes, <a href="http://www.devalco.de/table_8.htm">Distribution of Primes</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/ModularPrimeCountingFunction.html">Modular Prime Counting Function</a>

%t p = Select[Table[8 i + 7, {i, 0, 10^7}], PrimeQ[#] &]; Table[Count[p, x_ /; x < 10^n], {n, 7}] (* _Robert Price_, May 28 2019 *)

%Y Cf. A091126, A091127, A091128.

%K nonn,more

%O 1,2

%A _Eric W. Weisstein_, Dec 19 2003

%E a(10) from _Robert G. Wilson v_, Dec 22 2003

%E a(11)-a(14) from Bernhard Helmes (pi(AT)devalco.de), Apr 21 2010

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Last modified July 11 20:03 EDT 2020. Contains 335652 sequences. (Running on oeis4.)