|
Search: id:A073277
|
|
|
| A073277 |
|
Irregular primes with irregularity index two. |
|
+0
7
|
|
| 157, 353, 379, 467, 547, 587, 631, 673, 691, 809, 929, 1291, 1297, 1307, 1663, 1669, 1733, 1789, 1933, 1997, 2003, 2087, 2273, 2309, 2371, 2383, 2423, 2441, 2591, 2671, 2789, 2909, 2957, 3391, 3407, 3511, 3517, 3533, 3539, 3559, 3593, 3617, 3637, 3851
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
REFERENCES
|
J. Buhler, R. Crandall, R. Ernvall, T. Metsankyla and M. A. Shokrollahi, Irregular Primes and Cyclotomic Invariants to 12 Million, J. Symbolic Computation 31, 2001, 89-96.
|
|
LINKS
|
T. D. Noe, Table of n, a(n) for n=1..10000 (from Buhler et al)
Bernoulli numbers, irregularity index of primes
|
|
MATHEMATICA
|
Do[p = Prime[n]; k = 1; c = 0; While[ 2*k < p - 3, If[ Mod[ Numerator[ BernoulliB[2*k]], p] == 0, c++ ]; k++ ]; If[ c == 2, Print[p]], {n, 3, 550} ]
|
|
CROSSREFS
|
Cf. A000928, A000367, A060974, A060975 and A073276.
Sequence in context: A140625 A142874 A060974 this_sequence A096708 A142833 A142478
Adjacent sequences: A073274 A073275 A073276 this_sequence A073278 A073279 A073280
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Robert G. Wilson v (rgwv(AT)rgwv.com), Jul 22 2002
|
|
|
Search completed in 0.002 seconds
|
