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A002147 Largest prime == 7 (mod 8) with class number 2n+1.
(Formerly M4402 N1857)
3
7, 31, 127, 487, 1423, 1303, 2143, 2647, 4447, 5527, 5647, 6703, 5503, 11383, 8863, 13687, 13183, 12007, 22807, 18127, 21487, 22303, 29863, 25303, 27127 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
COMMENTS
Apr 14 2008: David Broadhurst says: I computed class numbers for prime discriminants with |D| < 10^9, but stopped when the first case with |D| > 5*10^8 was observed. That factor of 2 seems to me to be a reasonable margin of error, when you look at the pattern of what is included.
REFERENCES
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).
LINKS
David Broadhurst, Table of n, a(n) for n = 0..2246 (conjectural; see comment).
CROSSREFS
Cf. A002146.
Sequence in context: A036280 A153005 A056909 * A169785 A255282 A303449
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified July 16 19:40 EDT 2024. Contains 374358 sequences. (Running on oeis4.)