1,1

4 is in the sequence because 4!*4^4-1=6143 is prime.

Do[If[PrimeQ[n^n*n!-1], Print[n]], {n, 700}]

Cf. A002981, A002982.

Sequence in context: A153661 A067195 A080230 this_sequence A058779 A132473 A053037

Adjacent sequences: A084911 A084912 A084913 this_sequence A084915 A084916 A084917

more,nonn

Farideh Firoozbakht (f.firoozbakht(AT)sci.ui.ac.ir), Jul 14 2003