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A139571
Numbers with 31 divisors.
20
1073741824, 205891132094649, 931322574615478515625, 22539340290692258087863249, 17449402268886407318558803753801, 2619995643649944960380551432833049
OFFSET
1,1
COMMENTS
30th powers of primes. The n-th number with p divisors is equal to the n-th prime raised to power p-1, where p is prime.
Start of 31st row of A073915. - R. J. Mathar, Jun 27 2009, Jun 28 2009
FORMULA
a(n) = A000040(n)^(31-1) = A000040(n)^30.
a(n) = A122971(A000040(n)). - R. J. Mathar, Jun 27 2009
MATHEMATICA
Prime[Range[11]]^30 (* Vladimir Joseph Stephan Orlovsky, May 05 2011 *)
PROG
(PARI) a(n)=prime(n)^30 \\ Charles R Greathouse IV, Jun 19 2016
CROSSREFS
Cf. A073915, A122971, A137493 (30 divs), A175742 (32 divs).
Sequence in context: A017494 A017626 A122971 * A134595 A217610 A219319
KEYWORD
nonn,easy
AUTHOR
Omar E. Pol, May 07 2008
STATUS
approved