A068935 Numbers having the sum of distinct prime factors less than the sum of exponents in prime factorization, A008472(n) < A001222(n).

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

Author

Reinhard Zumkeller, Mar 08 2002

Keywords

• nonn

Examples

			144 is included because 144 = 2^4 * 3^2 and 2+3 < 4+2.
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A068936, A054411, A068937, A068938.

Programs

Mathematica

okQ[n_]:=Module[{tfi=Transpose[FactorInteger[n]]},Total[First[tfi]]Harvey P. Dale, Jan 17 2011 *)

PARI

isok(n) = vecsum(factor(n)[,1]) < bigomega(n); \\ Michel Marcus, Apr 25 2016

Extensions

More terms from Michel Marcus, Apr 25 2016