1,2

Alois P. Heinz, Table of n, a(n) for n = 1..65536

(PARI) A085089(n)=#Set(apply(t->vecsort(factor(t)[, 2]), [1..n])) \\ Not very efficient for large n > 10^5, but very quick up to the point where stack overflow occurs. - M. F. Hasler, Jul 16 2019

Cf. A025487.

Cf. A025488(n) = a(2^n); A124832 (table of the distinct prime signatures in the order they occur).

Sequence in context: A282711 A035100 A303594 * A228720 A219652 A069924

Adjacent sequences: A085086 A085087 A085088 * A085090 A085091 A085092

easy,nonn

Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jul 02 2003

More terms from Ray Chandler, Aug 17 2003

approved