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A189987 Numbers with prime factorization pq^6. 5
192, 320, 448, 704, 832, 1088, 1216, 1458, 1472, 1856, 1984, 2368, 2624, 2752, 3008, 3392, 3645, 3776, 3904, 4288, 4544, 4672, 5056, 5103, 5312, 5696, 6208, 6464, 6592, 6848, 6976, 7232, 8019, 8128, 8384, 8768, 8896, 9477, 9536, 9664, 10048, 10432, 10688 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

Will Nicholes, Prime Signatures

Index to sequences related to prime signature

FORMULA

Solutions of the equation tau(n^13)=79*tau(n). - Paolo P. Lava, Mar 15 2013

MAPLE

with(numtheory);

A189987:=proc(q) local n;

for n from 1 to q do if tau(n^13)=79*tau(n) then print(n); fi; od; end:

A189987(10^10);  # Paolo P. Lava, Mar 15 2013

MATHEMATICA

f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 6}; Select[Range[30000], f]

PROG

(PARI) list(lim)=my(v=List(), t); forprime(p=2, (lim\2)^(1/6), t=p^6; forprime(q=2, lim\t, if(p==q, next); listput(v, t*q))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Jul 20 2011

CROSSREFS

Cf. A030632, A092759.

Sequence in context: A045077 A234135 A030632 * A229361 A232940 A254854

Adjacent sequences:  A189984 A189985 A189986 * A189988 A189989 A189990

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, May 03 2011

STATUS

approved

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Last modified January 16 15:53 EST 2019. Contains 319195 sequences. (Running on oeis4.)