A091129 Number of primes of the form 8k+7 less than 10^n.
1, 6, 43, 308, 2399, 19669, 166237, 1440406, 12711702, 113766208, 1029523130, 9401993203, 86516416092, 801235499451
Offset: 1
Links
- Bernhard Helmes, Distribution of Primes
- Eric Weisstein's World of Mathematics, Modular Prime Counting Function
Programs
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Mathematica
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 *)
Extensions
a(10) from Robert G. Wilson v, Dec 22 2003
a(11)-a(14) from Bernhard Helmes (pi(AT)devalco.de), Apr 21 2010
Comments