A226479 Numbers n such that (sopf(n)*d(n))^2 = sigma(n) where sopf(n) = sum of distinct prime factors of n (A008472) and d(n) = number of divisors of n.

22446139, 26116291, 28097023, 30236557, 31090489, 31124341, 39618558, 41628195, 49941589, 51777957, 61137673, 62224039, 66960589, 71096795, 71334867, 71585139, 72304400, 82266591, 83045869, 92346023, 92837591, 105183961, 114762567, 117908994, 123563821

Offset: 1

Author

Donovan Johnson, Jun 09 2013

Keywords

• nonn

Comments

Suggested by N. J. A. Sloane.

Examples

			n = 22446139 = 31*67*101*107. sopf(n) = 31+67+101+107 = 306. d(n) = 16. (sopf(n)*d(n))^2 = (306*16)^2 = 23970816 = sigma(n).
		

Links

• Donovan Johnson, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A000005, A000203, A006532, A008472, A126028, A226480.