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Search: id:A161769
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| A161769 |
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A positive integer n is included if the greatest common divisor of (the sum of the distinct primes dividing n) and (the sum of the exponents in the prime-factorization of n) is > 1. |
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1
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OFFSET
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1,1
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COMMENT
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n is included if A161606(n) is >= 2.
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EXAMPLE
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The prime factorization of 28 is 2^2 * 7^1. The sum of the distinct prime divisors of 28 is 2+7 = 9. The sum of the prime-factorization exponents of 28 is 2+1 = 3. Since GCD(9,3) = 3 is > 1, then 28 is included in this sequence.
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CROSSREFS
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A008472, A001222, A161606
Sequence in context: A163773 A076349 A152442 this_sequence A135658 A066862 A103540
Adjacent sequences: A161766 A161767 A161768 this_sequence A161770 A161771 A161772
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KEYWORD
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more,nonn
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AUTHOR
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Leroy Quet (q1qq2qqq3qqqq(AT)yahoo.com), Jun 18 2009
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