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A068935
Numbers having the sum of distinct prime factors less than the sum of exponents in prime factorization, A008472(n) < A001222(n).
6
8, 16, 32, 64, 81, 96, 128, 144, 192, 216, 243, 256, 288, 324, 384, 432, 486, 512, 576, 640, 648, 729, 768, 864, 972, 1024, 1152, 1280, 1296, 1458, 1536, 1600, 1728, 1944, 2048, 2187, 2304, 2560, 2592, 2916, 3072, 3200, 3456, 3584, 3888, 4000, 4096, 4374, 4608
OFFSET
1,1
LINKS
EXAMPLE
144 is included because 144 = 2^4 * 3^2 and 2+3 < 4+2.
MATHEMATICA
okQ[n_]:=Module[{tfi=Transpose[FactorInteger[n]]}, Total[First[tfi]]<Total[Last[tfi]]]
Select[Range[2500], okQ] (* Harvey P. Dale, Jan 17 2011 *)
PROG
(PARI) isok(n) = vecsum(factor(n)[, 1]) < bigomega(n); \\ Michel Marcus, Apr 25 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Mar 08 2002
EXTENSIONS
More terms from Michel Marcus, Apr 25 2016
STATUS
approved