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A055669
Number of prime Hurwitz quaternions of norm prime(n).
6
24, 96, 144, 192, 288, 336, 432, 480, 576, 720, 768, 912, 1008, 1056, 1152, 1296, 1440, 1488, 1632, 1728, 1776, 1920, 2016, 2160, 2352, 2448, 2496, 2592, 2640, 2736, 3072, 3168, 3312, 3360, 3600, 3648, 3792, 3936, 4032, 4176, 4320, 4368, 4608, 4656, 4752
OFFSET
1,1
COMMENTS
Number of vectors of norm p in D_4 lattice (cf. A004011).
REFERENCES
L. E. Dickson, Algebras and Their Arithmetics, Dover, 1960, Section 91.
LINKS
L. E. Dickson, Algebras and Their Arithmetics, Univ. of Chicago Press, 1923, Section 91 (page 147).
FORMULA
a(n) = 24 * (prime(n)+1) = 24 * A008864(n) for n >= 2.
MATHEMATICA
Join[{24}, 24(#+1)&/@Prime[Range[2, 50]]] (* Harvey P. Dale, Mar 12 2013 *)
CROSSREFS
Cf. A240068 (number of prime Lipschitz quaternions having norm prime(n)).
Sequence in context: A198387 A057102 A057103 * A370846 A335144 A209432
KEYWORD
nonn,easy,nice
AUTHOR
N. J. A. Sloane, Jun 09 2000
EXTENSIONS
More terms from David W. Wilson, May 02 2001
STATUS
approved