A217018 Partial sums of 3-almost primes which are again 3-almost primes, i.e., have exactly 3 not necessarily distinct prime factors.

8, 20, 964, 1825, 2074, 2637, 3614, 3786, 4503, 5283, 5495, 6414, 6652, 7138, 7383, 9485, 9764, 10330, 10615, 11191, 12427, 12749, 13074, 15475, 16195, 16930, 18446, 19233, 20855, 22108, 22959, 23387, 28273, 28747, 29222, 30676, 32695, 34798, 35871

Offset

1,1

Comments

Bigomega=3 analog of the semiprime version A092190. In sequence A086062 it was asked whether there are infinitely many such numbers.

Links

Table of n, a(n) for n=1..39.

Formula

A217018 = A086062 intersect A014612.

Prog

(PARI) A217018(n, list=0, N=0, S=0)={until(!n--, until(bigomega(S+=N)==3, until(bigomega(N++)==3, )); list&print1(S", ")); S} \\ - M. F. Hasler, Sep 29 2012

Crossrefs

Sequence in context: A230987 A060668 A221067 * A108235 A130021 A003864

Adjacent sequences: A217015 A217016 A217017 * A217019 A217020 A217021

Keyword

nonn

Author

M. F. Hasler, Sep 23 2012

Status

approved