A113767 Values of the exponents in A084435.

0, 1, 2, 1, 5, 1, 1, 29, 3, 37, 31, 227, 835, 115, 7615, 6071, 218431

Offset: 1

Author

Ken Takusagawa, Jan 19 2006

Keywords

• nonn
• hard
• more

Comments

If A084435 ever hits a Sierpinski number, the sequence is finite.

a(18) > 10^6. - Harsh R. Aggarwal, Sep 14 2024

Links

• Eric Weisstein's World of Mathematics, Sierpinski Number of the Second Kind.

Crossrefs

Cf. A084435, A113334, A121799.

Programs

PARI

a=2;for(x=1,16,for(k=0,1000000,p=2^k*a+1;if(isprime(p),print(k);break));a=p)

Extensions

a(16)-a(17) from Harsh R. Aggarwal, Apr 11 2018