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%I #11 Jul 17 2019 07:21:43
%S 1,2,2,3,3,4,4,5,5,5,5,6,6,6,6,7,7,7,7,7,7,7,7,8,8,8,8,8,8,9,9,10,10,
%T 10,10,11,11,11,11,11,11,11,11,11,11,11,11,12,12,12,12,12,12,12,12,12,
%U 12,12,12,13,13,13,13,14,14,14,14,14,14,14,14,15,15,15,15,15,15,15,15,15
%N Number of distinct prime signatures arising up to n.
%H Alois P. Heinz, <a href="/A085089/b085089.txt">Table of n, a(n) for n = 1..65536</a>
%o (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
%Y Cf. A025487.
%Y Cf. A025488(n) = a(2^n); A124832 (table of the distinct prime signatures in the order they occur).
%K easy,nonn
%O 1,2
%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jul 02 2003
%E More terms from _Ray Chandler_, Aug 17 2003
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