1,1

Dario Alpern, Factorization using the Elliptic Curve Method.

a(2)=8023 because 8023=71*113=2^13-13^2=2^A099481(2)-A099481(2)^2.

Cf. A024012 2^n-n^2, A099481 2^n-n^2 is a semiprime, A072180 2^n-n^2 is prime, A075896 primes of the form 2^n-n^2.

Adjacent sequences: A099479 A099480 A099481 this_sequence A099483 A099484 A099485

Sequence in context: A107564 A135648 A133301 this_sequence A141593 A031766 A031632

nonn

Hugo Pfoertner (hugo(AT)pfoertner.org), Oct 18 2004