1,1

Records are for n's such that A071904(n) = squares of primes.

a(n) = A020639(A071904(n)). [Reinhard Zumkeller, Oct 10 2011]

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

A071904(1)=9, hence a(1)=3, A071904(4)=25, hence a(4)=5.

nn=501; With[{ci=Complement[Range[9, nn, 2], Prime[Range[PrimePi[nn]]]]}, FactorInteger[ #][[1, 1]]&/@ci] (* Harvey P. Dale, Nov 30 2012 *)

Cf. A014076, A071904.

Sequence in context: A002373 A236569 A103153 * A318240 A262289 A096918

Adjacent sequences: A162019 A162020 A162021 * A162023 A162024 A162025

nonn

Zak Seidov, Jun 25 2009

Corrected example a(4)=5 Francesco Antoni (francesco_antoni(AT)yahoo.com), Aug 04 2010

approved