1,1

This is the 3-almost prime analogue of A114522 "numbers n such that sum of distinct prime divisors of n is prime."

{k such that A008472(k) is an element of A014612}. {k such that sopf(k) is an element of A014612}. {k = Product(Prime(j)^e_j) such that Sum(Prime(j)) is in A014612}. {k such that A008472(k) is an element of Union[8-almost primes (A014613), 12-almost primes (A069273), 18-almost primes (A069279), 20-almost primes (A069281), 27-almost primes]...

a(1) = 15 because 15 = 3 * 5, and 3 + 5 = 8 = 2^3 is a 3-almost prime.

a(2) = 35 because 15 = 5 * 7, and 5 + 7 = 12 = 2^2 * 3 is a 3-almost prime.

a(3) = 42 because 42 = 2 * 3 * 7, and 2 + 3 + 7 = 12 = 2^2 * 3 is a 3-almost prime.

a(4) = 45 because 45 = 3^2 * 5, and 3 + 5 = 8 = 2^3 is a 3-almost prime.

a(5) = 51 because 51 = 3 * 17, and 3 + 17 = 20 = 2^2 * 5 is a 3-almost prime.

a(6) = 65 because 65 = 5 * 13, and 5 + 13 = 18 = 2 * 3^2 is a 3-almost prime.

Cf. A008472, A014612, A014613, A069273, A069279, A069281, A114522.

Sequence in context: A134335 A080774 A146319 this_sequence A130871 A143202 A108668

Adjacent sequences: A114985 A114986 A114987 this_sequence A114989 A114990 A114991

easy,nonn

Jonathan Vos Post (jvospost3(AT)gmail.com), Feb 22 2006