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A227799 Number of composites removed in each step of the Sieve of Eratosthenes for 10^10. 3
4999999999, 1666666666, 666666666, 380952380, 207792207, 159840159, 112828348, 95013343, 74358271, 56409724, 50950713, 41311372, 36273411, 33742734, 30153115, 26170720, 23065826, 21931483, 19640105, 18256894, 17506397, 15954848, 14993294, 13813524, 12531256 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) = the number of composites <= 10^10 for which the n-th prime is the least prime factor.

pi(sqrt(10^10)) = the number of terms of this sequence.

The sum of a(n) for n = 1..3401 = A000720(10^10) + A065855(10^10).

LINKS

Eric F. O'Brien, Table of n, a(n) for n = 1..9592

EXAMPLE

a(1) = 10^10 \ 2 - 1.

a(2) = 10^10 \ 3 - 10^10 \ (2*3) - 1.

a(3) = 10^10 \ 5 - 10^10 \ (2*5) - 10^10 \ (3*5) + 10^10 \ (2*3*5) - 1.

a(4) = 10^10 \ 7 - 10^10 \ (2*7) - 10^10 \ (3*7) - 10^10 \ (5*7) + 10^10 \ (2*3*7) + 10^10 \ (2*5*7) + 10^10 \ (3*5*7) - 10^10 \ (2*3*5*7) - 1.

CROSSREFS

Cf. A133228, A145538, A145539, A145540, A145583, A227155, A227797, A227798, A145532, A145533, A145534, A145535, A145536, A145537.

Sequence in context: A233615 A217146 A072018 * A216013 A158726 A338394

Adjacent sequences:  A227796 A227797 A227798 * A227800 A227801 A227802

KEYWORD

nonn,fini

AUTHOR

Eric F. O'Brien, Jul 31 2013

STATUS

approved

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Last modified March 5 16:55 EST 2021. Contains 341827 sequences. (Running on oeis4.)