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A179664 Products of the 7th power of a prime and a distinct prime (p^7*q). 12
384, 640, 896, 1408, 1664, 2176, 2432, 2944, 3712, 3968, 4374, 4736, 5248, 5504, 6016, 6784, 7552, 7808, 8576, 9088, 9344, 10112, 10624, 10935, 11392, 12416, 12928, 13184, 13696, 13952, 14464, 15309, 16256, 16768, 17536, 17792, 19072, 19328 (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^9)=40*tau(n). - Paolo P. Lava, Mar 18 2013

MAPLE

A179664:=proc(q) local n;

for n from 1 to q do if tau(n^9)=40*tau(n) then print(n); fi; od; end:

A179664(10^10);  # Paolo P. Lava, Mar 18 2013

MATHEMATICA

f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 7}; Select[Table[n, {n, 8!}], f[ # ]&]

PROG

(PARI) list(lim)=my(v=List(), t); forprime(p=2, (lim\2)^(1/7), t=p^7; forprime(q=2, lim\t, if(p==q, next); listput(v, t*q))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Jul 20 2011

CROSSREFS

Sequence in context: A046491 A046492 A110296 * A212430 A134175 A233886

Adjacent sequences:  A179661 A179662 A179663 * A179665 A179666 A179667

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jul 23 2010

STATUS

approved

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Last modified October 18 18:56 EDT 2019. Contains 328197 sequences. (Running on oeis4.)