A227799 Number of composites removed in each step of the Sieve of Eratosthenes for 10^10.

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

Offset: 1

Author

Eric F. O'Brien, Jul 31 2013

Keywords

• nonn
• fini

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).

Examples

			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.
		

Links

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

Crossrefs

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