1,2

a(28) > 10^12. - Lucas A. Brown, Oct 18 2020

Table of n, a(n) for n=1..27.

a(3) = 5 is a term because the 5th semiprime is 14 and 14 == 4 (mod 5).

Cf. A001358.

Sequence in context: A111491 A331402 A284605 * A163499 A086218 A202637

Adjacent sequences: A106126 A106127 A106128 * A106130 A106131 A106132

hard,more,nonn

Shyam Sunder Gupta, May 07 2005

a(21)-a(27) by Lucas A. Brown, Oct 18 2020

a(1), a(2) by Lucas A. Brown, Oct 19 2020

approved