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A244509
Order of GL_2(p), the general linear group over F_p, where p runs through the primes.
3
6, 48, 480, 2016, 13200, 26208, 78336, 123120, 267168, 682080, 892800, 1822176, 2755200, 3337488, 4773696, 7738848, 11908560, 13615200, 19845936, 25048800, 28003968, 38450880, 46879728, 62029440, 87607296, 103020000, 111447648, 129843216, 139851360
OFFSET
1,1
LINKS
Abbey Bourdon, Ozlem Ejder, Yuan Liu, Frances Odumodu, Bianca Viray, On the level of modular curves that give rise to sporadic j-invariants, arXiv:1808.04520 [math.NT], 2018. See Table 7.2 (an extract of current sequence).
FORMULA
a(n) = (p-1)*p*(p^2-1) where p = prime(n).
a(n) = A127917(n)*(prime(n)-1).
Subsequence of A047927. - Michel Marcus, Nov 25 2014
EXAMPLE
For n=3 (p=5) we have a(3) = 4*5*(25-1) = 480.
MATHEMATICA
gl2psz[p_] := (p - 1) p (p^2 - 1); sqg = gl2psz/@Prime@Range[m]
Table[(Prime[n] - 1) Prime[n] (Prime[n]^2 - 1), {n, 30}] (* Vincenzo Librandi, Aug 15 2018 *)
PROG
(PARI) a(n) = { my(p=prime(n)); (p-1)*p*(p^2-1) } \\ Joerg Arndt, Nov 23 2014
(Magma) [(NthPrime(n)-1)*NthPrime(n)*(NthPrime(n)^2-1): n in [1..100]]; // Vincenzo Librandi, Aug 15 2018
CROSSREFS
Cf. A127917 (order of SL_2(p)), A047927.
Sequence in context: A319292 A261834 A226740 * A105627 A051578 A052639
KEYWORD
nonn
AUTHOR
John McGee, Nov 15 2014
STATUS
approved