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A116660
Integers in both sequences A075658 and A067028.
2
56, 60, 84, 90, 104, 126, 132, 135, 140, 150, 152, 156, 184, 189, 196, 198, 204, 220, 224, 225, 228, 234, 240, 248, 260, 276, 294, 296, 297, 306, 308, 315, 330, 336, 340, 342, 344, 348, 350, 351, 360, 364, 372, 375, 376, 380, 414, 416, 424, 441, 444, 459
OFFSET
1,1
COMMENTS
It could be argued that 1 should also be included in the sequence, if 0 is considered to be a composite, since the number of prime divisors (counted with multiplicity) of 1 and the sum of 1's distinct prime divisors are both 0.
LINKS
EXAMPLE
60 = 2^2 *3^1 *5^1. Both the number of prime divisors (counted with multiplicity), 2+1+1 = 4 and the sum of the distinct prime divisors, 2+3+5 = 10, are composite. So 60 is in the sequence.
MATHEMATICA
Select[Range[460], CompositeQ[Plus @@ (f = FactorInteger[#])[[;; , 1]]] && CompositeQ[Plus @@ f[[;; , 2]]] &] (* Amiram Eldar, Nov 14 2019 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, Feb 21 2006
EXTENSIONS
More terms from R. J. Mathar, Aug 31 2007
STATUS
approved