A029909 Starting with n (but omitting the primes), repeatedly sum prime factors (counted with multiplicity) until reaching a limit.

0, 4, 5, 5, 5, 7, 7, 5, 5, 5, 5, 5, 7, 13, 5, 7, 5, 5, 11, 7, 7, 5, 19, 7, 7, 7, 5, 11, 7, 5, 11, 7, 11, 5, 7, 5, 17, 11, 5, 13, 13, 31, 7, 5, 13, 7, 5, 5, 7, 5, 5, 7, 5, 13, 23, 5, 5, 13, 7, 43, 5, 13, 11, 7, 17, 13, 5, 5, 19, 5, 5, 13, 5, 17, 5, 13, 19, 5, 5, 13, 5, 11, 5, 5, 11, 5

Offset: 1

Author

Dann Toliver

Keywords

• nonn

Comments

Is this sequence generating ALL prime numbers (greater than 3) ? Also how many times each prime (greater than 3)is generated in this sequence? - Alexander R. Povolotsky, Nov 05 2008

Records appear to correspond to A006512 (n>2). - Bill McEachen, Jun 10 2025

Examples

			20 -> 2+2+5 = 9 -> 3+3 = 6 -> 2+3 = 5.
		

Links

• Paolo P. Lava, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A029908.