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A091129 Number of primes of the form 8k+7 less than 10^n. 4
1, 6, 43, 308, 2399, 19669, 166237, 1440406, 12711702, 113766208, 1029523130, 9401993203, 86516416092, 801235499451 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Computed by T. D. Noe, Dec 19 2003.

LINKS

Table of n, a(n) for n=1..14.

Bernhard Helmes, Distribution of Primes

Eric Weisstein's World of Mathematics, Modular Prime Counting Function

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 *)

CROSSREFS

Cf. A091126, A091127, A091128.

Sequence in context: A099322 A014989 A015552 * A091128 A025594 A098665

Adjacent sequences:  A091126 A091127 A091128 * A091130 A091131 A091132

KEYWORD

nonn,more

AUTHOR

Eric W. Weisstein, Dec 19 2003

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

STATUS

approved

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Last modified May 31 02:51 EDT 2020. Contains 334747 sequences. (Running on oeis4.)