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A072414 Non-Achilles numbers for which LCM of the exponents in the prime factorization of n is not equal to the maximum of the same exponents. +0
5
360, 504, 540, 600, 756, 792, 936, 1176, 1188, 1224, 1350, 1368, 1400, 1404, 1440, 1500, 1656, 1836, 1960, 2016, 2052, 2088, 2160, 2200, 2232, 2250, 2400, 2484, 2520, 2600, 2646, 2664, 2904, 2952, 3024, 3096, 3132, 3168, 3240, 3348, 3384, 3400, 3500 (list; graph; listen)
OFFSET

1,1

COMMENT

Most members of this sequence fail to be Achilles numbers because they have at least one prime factor with multiplicity 1. There are also numbers in the sequence that fail to be Achilles numbers because they are perfect powers: these are precisely the proper powers of members of A072412, so the smallest such is 5184 = 2^6*3^4 = 72^2. - Franklin T. Adams-Watters (FrankTAW(AT)Netscap), Oct 09 2006

FORMULA

A051903(a[n]) is not equal A072411(a[n]) but the numbers are not in A052486.

EXAMPLE

m=504=2.2.2.3.3.7: exponent-set=E={3,2,1}, Max[E]=3 < LCM[E]=6, GCD[E]=Min[E]=1.

CROSSREFS

Cf. A005361, A051903, A051904, A052409, A072411, A072412, A052486.

Sequence in context: A137487 A069478 A060665 this_sequence A163569 A063067 A076205

Adjacent sequences: A072411 A072412 A072413 this_sequence A072415 A072416 A072417

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Jun 17 2002

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Last modified November 30 13:13 EST 2009. Contains 167758 sequences.


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