A222137 Primes of the form 2^p - p^2, where p is prime.

7, 79, 130783, 523927, 9007199254738183, 9671406556917033397642519, 215679573337205118357336120696157045389097155380324579848828881942199

Offset: 1

Author

Jaroslav Krizek, Feb 08 2013

Keywords

• nonn

Comments

Subsequence of A075896 (primes of the form 2^n - n^2).

Primes of the form 2^p - p^2 (p = prime) for p = 5, 7, 17, 19, 53, 83, 227, 461, 2221,... (all p <= 2455).

a(8) = 59542628... has 139 digits.

a(9) = 2^2221 - 2221^2 has 669 digits.

Examples

			130783 is in the sequence because it is prime and it is of the form 2^p - p^2 where p=17 is prime.
		

Crossrefs

Cf. A075896.

Programs

Mathematica

lst={}; Do[p=Prime[n]; If[PrimeQ[p=2^p-p^2], AppendTo[lst, p]], {n, 100}]; lst