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A000922
Primes p of the form 3k+1 such that -sqrt(p) < sum_{x=1..p} cos(2*Pi*x^3/p) < sqrt(p).
(Formerly M4890 N2096)
3
13, 19, 37, 61, 109, 157, 193, 241, 283, 367, 373, 379, 397, 487, 571, 613, 619, 733, 739, 859, 883, 907, 1009, 1033, 1051, 1129, 1153, 1201, 1291, 1297, 1303, 1399, 1429, 1453, 1459, 1489, 1549, 1669, 1699, 1753, 1783, 1831, 1861, 1933, 1951, 1987, 2011
OFFSET
1,1
REFERENCES
H. Hasse, Vorlesungen über Zahlentheorie. Springer-Verlag, NY, 1964, p. 482.
G. B. Mathews, Theory of Numbers, 2nd edition. Chelsea, NY, p. 228.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
EXAMPLE
13 is here because the sum of cos(2*Pi*x^3/13) = 1.8217, between -sqrt(13) and +sqrt(13).
CROSSREFS
KEYWORD
nonn
EXTENSIONS
Edited by Don Reble, May 26 2007
STATUS
approved