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A309520 Primes p for which h1(p)/G(p) has a record value. 0
3, 5, 7, 11, 23, 73, 89, 179, 233, 761, 1451, 2741, 4391, 5231, 42611, 198221, 305741, 6766811, 1326662801, 1979990861, 4735703723, 9697282541, 35285447111, 45169368641, 169684421321, 187946428721 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
h1 is given by A000927, and G(p) = 2*p*(p/(4*Pi^2))^((p-1)/4).
a(1)-a(12) from Fung et al., a(13)-a(14) from Shokrollahi, a(15)-a(17) from Broadhurst, a(18) from Languasco et al. and Broadhurst, a(19)-a(26) from Broadhurst.
LINKS
David Broadhurst, Kummer ratio champions with p < 10^12, July 22 2021.
Gilbert Fung, Andrew Granville and Hugh C. Williams, Computation of the first factor of the class number of cyclotomic fields, Journal of Number Theory, Volume 42, Issue 3, November 1992, Pages 297-312. See Table IV A p. 304.
Alessandro Languasco, Pieter Moree, Sumaia Saad Eddin and Alisa Sedunova, Computation of the Kummer ratio of the class number for prime cyclotomic fields, arXiv:1908.01152 [math.NT], 2019.
M. A. Shokrollahi, Relative class number of imaginary Abelian fields of prime conductor below 10000, Math. Comp. 68 (1999), 1717-1728. See Table 4 p. 1726.
PROG
(PARI) h1(p) = if (p<5, 1, abs( matdet(matrix((p-1)/2-2, (p-1)/2-2, i, j, ((i+2)*(j+2))\p - ((i+1)*(j+2))\p)) )); \\ A000927
G(p) = 2*p*(p/(4*Pi^2))^((p-1)/4);
lista(nn) = {my(m = 0, nm); for (n=2, nn, p = prime(n); if ((nm = h1(p)/G(p)) > m, print1(p, ", "); m = nm); ); }
CROSSREFS
Cf. A000927 (h1), A073010 (value for p=3).
Sequence in context: A360567 A226017 A303705 * A344411 A265687 A023368
KEYWORD
nonn,more
AUTHOR
Michel Marcus, Aug 06 2019
EXTENSIONS
Missing terms 42611, 198221, 305741 and terms larger than 6766811 added by Alessandro Languasco on behalf of David Broadhurst, Jul 24 2021
STATUS
approved

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Last modified April 19 19:02 EDT 2024. Contains 371798 sequences. (Running on oeis4.)