A183075 Numbers of the form 2^k - 1 for which each prime divisor has the form 4j + 3.
1, 3, 7, 31, 63, 127, 1023, 8191, 16383, 32767, 131071, 524287, 67108863, 1073741823, 2147483647, 17179869183, 274877906943, 8796093022207, 2251799813685247, 2305843009213693951
Offset: 1
Examples
63 = 2^6 - 1 = 3^2 * 7, and 3 and 7 have the form 4j + 3.
Links
- Amiram Eldar, Table of n, a(n) for n = 1..54
- S. S. Wagstaff, Jr., The Cunningham Project.
Crossrefs
Formula
a(n) = 2^A183071(n) - 1.
Comments