A172086 Numerators of sum (C(n) = A051716/A051717) + (1 followed by first differences A172083/A051717 of Bernoulli numbers).

2, -2, 1, -1, -1, 1, 1, -1, -1, 1, 5, -5, -691, 691, 7, -7, -3617, 3617, 43867, -43867, -174611, 174611, 854513, -854513, -236364091, 236364091, 8553103, -8553103, -23749461029, 23749461029, 8615841276005, -8615841276005, -7709321041217, 7709321041217, 2577687858367, -2577687858367

Offset: 0

Author

Paul Curtz, Jan 25 2010

Keywords

• sign
• frac

Comments

Denominators: 1, 1, 3, 3, 15, 15, 21, 21, 15, 15, 33, 33, 1365, 1365, ... = A001897 with terms repeated. See A000367/A002445.

Crossrefs

Cf. A000367, A001897, A002445, A027641, A051716, A051717

Extensions

Name edited by Michel Marcus, Jan 30 2021

Clarified definition, added more terms. - N. J. A. Sloane, Apr 22 2021