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A355877
Smallest prime p == 5 (mod 8) such that Q(sqrt(p)) has class number 2n+1.
2
5, 229, 1093, 2029, 7573, 12589, 8101, 13693, 54541, 18229, 75629, 91813, 59053, 65029, 72901, 146077, 127453, 199813, 169909, 209581, 439573, 189229, 197341, 324901, 378229, 596293, 430861, 352837, 712981, 1137229, 700573, 245029, 574261, 770533, 860701, 1432813, 1821877, 1092829
OFFSET
0,1
EXAMPLE
p = 229 is the smallest prime congruent to 5 modulo 8 such that Q(sqrt(p)) has class number 3, so a(1) = 229.
PROG
(PARI) a(n) = forprime(p=2, oo, if(p%8==5 && qfbclassno(p)==2*n+1, return(p)))
CROSSREFS
Cf. A355878.
Similar sequences: A355876 (p == 1 (mod 8)), A002148 (p == 3 (mod 8)), A002146 (p == 7 (mod 8)).
Sequence in context: A002142 A355878 A103732 * A065757 A157776 A147540
KEYWORD
nonn
AUTHOR
Jianing Song, Jul 20 2022
STATUS
approved