A212290 Difference between the smallest 10^n-bit prime and 2^(10^n-1).

9, 255, 1239, 5895, 221961

Offset: 1

Author

Charles R Greathouse IV, Jun 16 2012

Keywords

• nonn
• hard

Comments

a(5) found by Serge Batalov, Jun 11 2012.

Examples

			2^99+255 is the smallest 100-bit prime, 2^999+1239 is the smallest 1000-bit prime, etc.
		

Links

• Henri Lifchitz, Renaud Lifchitz, Probable Primes Top 10000.

Crossrefs

Binary analog of A096548.

Programs

PARI

a(n)=nextprime(2^(10^n-1))-2^(10^n-1)