A092681 Least number 2k such that p^2 divides the numerator of the Bernoulli number B(2k), where p is the n-th irregular prime, A000928(n).

284, 914, 3292, 5768, 228, 12112, 11082, 6302, 11498, 40220, 34724, 51976, 1434, 74750, 67316, 21508, 63532, 39378, 67066, 64012, 91576, 137766, 137552, 105582, 158838, 147660, 175758, 194776, 173842, 102148, 132072, 107112, 127736, 29248

Offset

1,1

Comments

The ordered-pair (p(n),a(n)), where p(n) is the n-th irregular prime, is called a second-order irregular pair. Some irregular primes, such as 157, have more than one pair. See A091887 for a count of the pairs for each irregular prime.

Links

Table of n, a(n) for n=1..34.

Bernd Kellner, On irregular pairs of higher order (in German)

Crossrefs

Cf. A000928, A035112, A091887, A092682.

Sequence in context: A061310 A333930 A259996 * A090789 A234970 A260087

Adjacent sequences: A092678 A092679 A092680 * A092682 A092683 A092684

Keyword

nonn

Author

T. D. Noe, Mar 03 2004

Status

approved