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A067582 Nonprime values of n such that bigomega(n)^omega(n)=omega(n)^bigomega(n) where bigomega(n) is the number of prime factors of n (counted with multiplicity) and omega(n) the number of distinct prime factors of n. 1
1, 6, 10, 14, 15, 21, 22, 24, 26, 30, 33, 34, 35, 36, 38, 39, 40, 42, 46, 51, 54, 55, 56, 57, 58, 62, 65, 66, 69, 70, 74, 77, 78, 82, 85, 86, 87, 88, 91, 93, 94, 95, 100, 102, 104, 105, 106, 110, 111, 114, 115, 118, 119, 122, 123, 129, 130, 133, 134, 135, 136, 138, 141 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Consists of nonprime squarefree numbers A000469(n) and numbers of the forms p*q^3 and p^2*q^2 for distinct primes p and q. (The solutions in positive integers of x^y=y^x are x=y and {x,y}={2,4}. The first case gives the squarefree numbers; the second gives the other two forms.)

LINKS

Table of n, a(n) for n=1..63.

PROG

(PARI) is(n)=my(f=factor(n)[, 2], b=vecsum(f), o=#f); b!=1 && b^o==o^b \\ Charles R Greathouse IV, Oct 15 2015

CROSSREFS

Sequence in context: A066073 A339438 A268376 * A229153 A119847 A279458

Adjacent sequences:  A067579 A067580 A067581 * A067583 A067584 A067585

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Jan 30 2002

EXTENSIONS

Edited by Dean Hickerson, Jun 18 2002

STATUS

approved

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Last modified March 4 20:58 EST 2021. Contains 341811 sequences. (Running on oeis4.)