OFFSET
1,1
COMMENTS
Product_{n >= 2, m_n = (a(n) mod 4) - 2} ((a(n) + 1) / (a(n) - 1))^m_n = 209865342976 / 209844223875. - Dimitris Valianatos, May 13 2020
LINKS
T. D. Noe, Table of n, a(n) for n = 1..1000
Xavier Gourdon and Pascal Sebah, Some Constants from Number theory.
Will Nicholes, Prime Signatures.
FORMULA
Sum_{n>=1} 1/a(n) = P(9) = 0.0020044675... (A085969). - Amiram Eldar, Jul 27 2020
From Amiram Eldar, Jan 24 2021: (Start)
Product_{n>=1} (1 - 1/a(n)) = 1/zeta(9) = 1/A013667. (End)
EXAMPLE
a(1) = 512 since the ninth power of the first prime is 2^9 = 512. - Wesley Ivan Hurt, Mar 27 2014
MAPLE
MATHEMATICA
Array[Prime[ # ]^9&, 30]
Prime[Range[30]]^9 (* Harvey P. Dale, Jul 20 2024 *)
PROG
(PARI) a(n)=prime(n)^9 \\ Charles R Greathouse IV, Jul 20 2011
(Magma) [p^9: p in PrimesUpTo(300)]; // Vincenzo Librandi, Mar 27 2014
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vladimir Joseph Stephan Orlovsky, Jul 23 2010
STATUS
approved