1,2

Lucas A. Brown, Table of n, a(n) for n = 1..47

a(3) = 6 is a term because the 6th semiprime is 15 and 15 == 3 (mod 6).

Cf. A001358.

Sequence in context: A184390 A130317 A019467 * A119186 A119115 A079653

Adjacent sequences: A106125 A106126 A106127 * A106129 A106130 A106131

hard,nonn

Shyam Sunder Gupta, May 07 2005

a(28)-a(30) from Donovan Johnson, Oct 29 2008

a(1), a(2), and a(31)-a(47) by Lucas A. Brown, Oct 19 2020

approved