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A307117
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Numbers x that are equal to lpf(x)*gpf(x)*(lpf(x)+gpf(x))/2, where lpf(x) and gpf(x) are the least and the greatest prime factors of x: A020639 and A006530.
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0
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8, 27, 105, 125, 231, 343, 627, 897, 935, 1331, 1581, 1729, 2197, 2465, 2967, 3525, 4123, 4301, 4715, 4913, 5487, 6859, 7035, 7685, 7881, 9717, 10707, 11339, 12167, 14993, 16377, 17353, 17655, 20213, 20915, 23779, 24389, 24765, 25327, 26331, 26765, 29341, 29607
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OFFSET
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1,1
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COMMENTS
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This is A307108 with terms such that lpf(x)=gpf(x), that is, with cubes of primes.
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LINKS
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CROSSREFS
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Cf. A262723 is the subsequence with terms such that lpf(x)!=gpf(x), and (lpf(x)+gpf(x))/2 a prime.
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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