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A102308
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If n = product{primes p(k)|n} p(k)^b(n,p(k)), where p(k) is the k-th prime that divides n (when these primes are listed from smallest to largest) and each b(n,p(k)) is a positive integer, then the sequence contains the non-prime-powers n such that p(k)^b(n,p(k)) > p(k+1) for all k, 1<=k<= -1 + number of distinct prime divisors of n.
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1
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12, 24, 36, 40, 45, 48, 56, 63, 72, 80, 96, 108, 112, 135, 144, 160, 175, 176, 180, 189, 192, 200, 208, 216, 224, 225, 252, 275, 288, 297, 320, 324, 325, 351, 352, 360, 384, 392, 400, 405, 416, 425, 432, 441, 448, 459, 475, 504, 513, 539, 540, 544, 567, 575
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| 252 is factored as 2^2 * 3^2 * 7^1. Since 2^2 > 3 and 3^2 > 7, then 252 is in the sequence. On the other hand, 60 is factored as 2^2 * 3^1 * 5^1. Even though 2^2 > 3, 3^1 is not > 5. So 60 is not in the sequence.
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CROSSREFS
| Cf. A143907
A057715 [From Ray Chandler (rayjchandler(AT)sbcglobal.net), Nov 06 2008]
Sequence in context: A195556 A083547 A009185 * A103291 A103292 A059691
Adjacent sequences: A102305 A102306 A102307 * A102309 A102310 A102311
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KEYWORD
| nonn
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AUTHOR
| Leroy Quet Sep 04 2008
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EXTENSIONS
| Extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Nov 06 2008
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