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 A071175 Numbers n such that product of exponents = sum of prime factors. 3

%I

%S 4,27,96,486,640,1440,2025,2400,2744,3024,3125,3528,3584,4032,4536,

%T 4860,5292,5625,9408,11907,12150,12348,14256,15360,16464,17424,20412,

%U 22400,22464,25344,31360,32805,36504,37500,39204,55566,56250,57624

%N Numbers n such that product of exponents = sum of prime factors.

%e 55566 = 2^1*3^4*7^3 and 1*4*3 = 2+3+7 hence 55566 is in the sequence.

%o (PARI) for(n=1,200000,o=omega(n); if(prod(i=1,o, component(component(factor(n),2),i))==sum(i=1,o, component(component(factor(n),1),i)),print1(n,",")))

%Y Cf. A054411, A054412.

%K easy,nonn

%O 1,1

%A _Benoit Cloitre_, Jun 10 2002

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Last modified January 16 06:59 EST 2019. Contains 319188 sequences. (Running on oeis4.)