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A072413 Numbers k such that the LCM of exponents in the prime factorization of k does not equal the product of the exponents. 2
36, 100, 144, 180, 196, 216, 225, 252, 300, 324, 396, 400, 441, 450, 468, 484, 576, 588, 612, 676, 684, 700, 720, 784, 828, 882, 900, 980, 1000, 1008, 1044, 1080, 1089, 1100, 1116, 1156, 1200, 1225, 1260, 1296, 1300, 1332, 1444, 1452, 1476, 1512, 1521 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Michael De Vlieger, Table of n, a(n) for n = 1..10000

FORMULA

A005361(a(n)) != A072411(a(n)).

EXAMPLE

k = 36 = 2*2*3*3; exponent set = {2,2}; LCM = 2, product = 4.

MATHEMATICA

Select[Range@ 1600, LCM @@ # != Times @@ # &@ Map[Last, FactorInteger@ #] &] (* Michael De Vlieger, May 15 2016 *)

PROG

(PARI) is(n)=my(f=factor(n)[, 2]); n>9 && lcm(f)!=factorback(f) \\ Charles R Greathouse IV, Jan 14 2017

CROSSREFS

Cf. A005361, A051903, A051904, A052409, A052486, A072411-A072414.

Sequence in context: A114819 A137945 A250812 * A131605 A296204 A063734

Adjacent sequences:  A072410 A072411 A072412 * A072414 A072415 A072416

KEYWORD

nonn

AUTHOR

Labos Elemer, Jun 17 2002

STATUS

approved

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Last modified April 19 20:37 EDT 2021. Contains 343117 sequences. (Running on oeis4.)