OFFSET
1,1
COMMENTS
a(n) is the order of the matrix group SL(2,prime(n)). - Tom Edgar, Sep 28 2015
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..10000
J. B. Marshall, On the extension of Fermat's theorem to matrices of order n, Proceedings of the Edinburgh Mathematical Society 6 (1939) 85-91. See (11) page 90-91 when p=2.
FORMULA
a(n) = prime(n)*(prime(n)^2-1). - Tom Edgar, Sep 28 2015
a(n) = 2 * A117762(n), for n > 1. - Altug Alkan, Sep 28 2015
From Amiram Eldar, Nov 22 2022: (Start)
Product_{n>=1} (1 + 1/a(n)) = A065487.
Product_{n>=1} (1 - 1/a(n)) = A065470. (End)
MATHEMATICA
Table[(Prime[n] + 1) Prime[n](Prime[n] - 1), {n, 1, 100}]
PROG
(PARI) forprime(p=2, 1e3, print1(6*binomial(p+1, 3)", ")) \\ Charles R Greathouse IV, Jun 16 2011
(PARI) a(n) = prime(n)*(prime(n)^2-1);
vector(40, n, a(n)) \\ Altug Alkan, Sep 28 2015
(Magma) [6] cat [NthPrime(n)*(NthPrime(n)^2-1): n in [2..40]]; // Vincenzo Librandi, Sep 29 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Artur Jasinski, Feb 06 2007
STATUS
approved