1,2
Primes have negative signs in a(n). Differs from A055615 at a(30) = 30.
Cf. A140699, A054524, A140256, A055615.
Sequence in context: A063956 A128214 A145105 * A055615 A190621 A049268
Adjacent sequences: A140697 A140698 A140699 * A140701 A140702 A140703
sign
Mats O. Granvik and Gary W. Adamson (mgranvik(AT)abo.fi), May 24 2008