2,1

B(6), B(16) and B(18) are the first three Bernoulli numbers such that their index is equal to their decimal expansion periodic length, B(16) and B(18) being the smallest such pair of consecutive even index Bernoulli numbers.

Table of n, a(n) for n=2..101.

54.9711779448621553884711779448621553884...

RealDigits[BernoulliB[18], 10, 100] // First

Cf. A021046 (B(6)), A234355 (B(16)).

Sequence in context: A198609 A054508 A110617 * A102081 A068397 A236405

Adjacent sequences: A234353 A234354 A234355 * A234357 A234358 A234359

nonn,cons

Jean-François Alcover and Paul Curtz, Dec 24 2013

approved