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A139316 An integer n, n>=2, is in the sequence if (the sum of the exponents in the prime-factorization of n) divides (the sum of the distinct primes dividing n). 0
2, 3, 4, 5, 7, 11, 13, 15, 17, 19, 21, 23, 27, 28, 29, 31, 33, 35, 37, 39, 41, 42, 43, 47, 48, 51, 52, 53, 55, 57, 59, 61, 65, 67, 69, 71, 72, 73, 76, 77, 78, 79, 83, 84, 85, 87, 89, 91, 93, 95, 97, 98, 101, 103, 105, 107, 108, 109, 110, 111, 113, 114, 115, 119, 120, 123 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..66.

EXAMPLE

28 has the prime factorization 2^2 * 7^1. The sum of the exponents, 2+1=3, divides the sum of the distinct prime divisors, 2+7=9. So 28 is in the sequence.

MATHEMATICA

seddpQ[n_]:=Module[{fi=Transpose[FactorInteger[n]]}, Divisible[Total[ fi[[1]]], Total[ fi[[2]]]]]; Select[Range[2, 150], seddpQ] (* Harvey P. Dale, Apr 13 2015 *)

CROSSREFS

Sequence in context: A191876 A234719 A055464 * A062972 A231878 A036844

Adjacent sequences:  A139313 A139314 A139315 * A139317 A139318 A139319

KEYWORD

nonn

AUTHOR

Leroy Quet, Jun 07 2008

EXTENSIONS

More terms from D. S. McNeil, Mar 23 2009

STATUS

approved

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Last modified December 2 23:29 EST 2016. Contains 278694 sequences.