1,2

Also, exponent of 2 in -1+prime(n)^s if s is an exponent of the form 4k+2 (previous definition). - Michel Marcus, Dec 20 2013

Primes that give records for this sequence can be found in A233930. - Michel Marcus, Dec 20 2013

Table of n, a(n) for n=1..105.

a(1)=0 since -1+2^s is always odd...

(PARI) a(n) = valuation(prime(n)^2-1, 2); \\ Michel Marcus, Dec 20 2013

Cf. A007814, A023506, A091283, A091284.

Sequence in context: A080038 A121937 A003034 * A202708 A027684 A276864

Adjacent sequences: A091279 A091280 A091281 * A091283 A091284 A091285

nonn

Labos Elemer, Jan 20 2004

Definition modified by Michel Marcus, Dec 20 2013

approved