1,2

No more under 2000.

Flatten[Position[Table[PrimeQ[4^n + 9 I], {n, 1, 2000}], True]]

Sequence in context: A066847 A057887 A006049 this_sequence A113050 A097110 A116961

Adjacent sequences: A084538 A084539 A084540 this_sequence A084542 A084543 A084544

hard,nonn

Ed Pegg Jr (ed(AT)mathpuzzle.com), May 29 2003