A063529 a(n) = M(2^n-1), where M() is A029834, a discrete version of the Mangoldt function: if n is prime then floor(log(n)) else 0 and 2^n-1 is A000225.

0, 1, 1, 0, 3, 0, 4, 0, 0, 0, 0, 0, 9, 0, 0, 0, 11, 0, 13, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 21, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 42, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 61, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0

Offset: 1

Author

Jason Earls, Aug 01 2001

Keywords

• easy
• nonn

Crossrefs

Cf. A029832, A029833, A053821, A062590, A029834, A000225.

Programs

PARI

j=[]; for(n=1,150,j=concat(j, if(isprime(2^n-1),floor(log(2^n-1)),))); j