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A230869
Primes p such that the class number h-tilde_p^{+} of the real cyclotomic field Q(zeta_p + zeta_p^(-1)) is greater than 1.
2
163, 191, 229, 257, 277, 313, 349, 397, 401, 457, 491, 521, 547, 577, 607, 631, 641, 709, 733, 761, 821, 827, 829, 853, 857, 877, 937, 941, 953, 977, 1009, 1063, 1069, 1093, 1129, 1153, 1229, 1231, 1297, 1373, 1381, 1399, 1429, 1459, 1489, 1567, 1601, 1697, 1699, 1777, 1789, 1831, 1861, 1873, 1879, 1889, 1901, 1951
OFFSET
1,1
COMMENTS
Taken from the "Main Table" of Schoof.
There is a very slight chance that some primes are missing. In the unlikely event that the number that Schoof calls h-tilde_p is 1, while the actual class number h_p is actually not equal to 1, the prime p would be missing (see the Schoof and Miller articles for details).
CROSSREFS
Cf. A230870 (for the actual class numbers).
Sequence in context: A057604 A243532 A272984 * A132250 A303379 A142940
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Nov 06 2013
STATUS
approved