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 A060651 Smallest prime p such that Q(sqrt -p) has class number 2n +1. 0
 3, 23, 47, 71, 199, 167, 191, 239, 383, 311, 431, 647, 479, 983, 887, 719, 839, 1031, 1487, 1439, 1151, 1847, 1319, 3023, 1511, 1559, 2711, 4463, 2591, 2399, 3863, 2351, 3527, 3719, 3119, 5471, 2999, 4703, 6263, 4391, 3671, 3911, 4079, 5279, 6311, 4679 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS MATHEMATICA Note that all such primes are == (3 mod 4) << NumberTheory`NumberTheoryFunctions` a = Table[0, {101}]; Do[ c = ClassNumber[ -Prime[n] ]; If[ c < 102 && a[ [c] ] == 0, a[ [c] ] = Prime[n] ], {n, 2, 4000} ]; Table[ a[ [n] ], {n, 1, 101} ] CROSSREFS Cf. A002148. Cf. A002146. [From R. J. Mathar, Oct 05 2008] Sequence in context: A160022 A307530 A187094 * A146592 A107169 A297956 Adjacent sequences:  A060648 A060649 A060650 * A060652 A060653 A060654 KEYWORD nonn AUTHOR Robert G. Wilson v, Apr 17 2001 STATUS approved

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Last modified December 7 20:44 EST 2019. Contains 329849 sequences. (Running on oeis4.)