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A356531
Primes p == 1 (mod 23) which are norms of elements in the 23rd cyclotomic field.
0
599, 691, 829, 1151, 2347, 2393, 3037, 3313, 3359, 4463, 4831, 5107, 5521, 5659, 6763, 8741, 9109, 9661, 10627, 10949, 11593, 12743, 13249, 14537, 14767, 14951, 15319, 15733, 16883, 17573
OFFSET
1,1
COMMENTS
Primes which are norms of principal ideals in the 23rd cyclotomic ring of integers.
The class number of the 23rd cyclotomic field is 3, so about 1/3 of primes == 1 (mod 23) should be norms of principal ideals.
Is it true that a(n) == 1 (mod 46)? - Hugo Pfoertner, Aug 13 2022
REFERENCES
Reimer Bruchmann, Quadratic and cyclotomic rings of integers, March 26th, 2022, 487-534.
EXAMPLE
2347 is in this sequence since it is the norm of the element x^7-x^3-x-1 where x is a 23rd primitive root of unity.
PROG
(PARI) a(n)={K=bnfinit(polcyclo(23)); ct=0; p=1; while(ct<n, p=nextprime(p+1); if(p%23==1 && #bnfisintnorm(K, p)>0, ct++); ); return(p)}
CROSSREFS
Sequence in context: A095746 A135846 A035209 * A385191 A385188 A135847
KEYWORD
nonn
AUTHOR
Paul Vanderveen, Aug 10 2022
STATUS
approved