4,1

Table of n, a(n) for n=4..75.

[ seq(prevprime(prevprime(i)), i=4..60) ];

NextPrime[NextPrime[#, -1], -1]&/@Range[4, 80] (* Harvey P. Dale, Oct 01 2012 *)

a(n) = A007917(A007917(n-1)-1).

Sequence in context: A276119 A167755 A259788 * A072729 A057872 A059974

Adjacent sequences: A033299 A033300 A033301 * A033303 A033304 A033305

nonn

N. J. A. Sloane.

More terms from David Wasserman, Aug 13 2002

approved