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%I #7 Dec 01 2024 11:39:13
%S 105,110,130,154,165,170,182,190,195,230,231,238,255,266,273,285,286,
%T 290,310,322,345,357,370,374,385,399,406,410,418,429,430,434,435,442,
%U 455,465,470,483,494,506,518,530,555,561,574,590,595,598,602,609,610,615,627,638,645,646,651,658,663,665
%N Products of 3 distinct primes numbers (or sphenics) that are deficient.
%e 105 is a term because 105=3*5*7 is the product of three distinct primes and it is larger than the sum of its proper divisors (1+3+5+7+15+21+35=87).
%e 110 is a term because 110=2*5*11 is the product of three distinct primes and it is larger than the sum of its proper divisors (1+2+5+10+11+22+55=106).
%t q[n_] := Module[{f = FactorInteger[n]}, f[[;; , 2]] == {1, 1, 1} && Times @@ (1 + 1/f[[;; , 1]]) < 2]; Select[Range[1000], q] (* _Amiram Eldar_, Nov 28 2024 *)
%Y Intersection of A005100 and A007304.
%K nonn
%O 1,1
%A _Massimo Kofler_, Nov 28 2024