A086007 - OEIS

%I #8 Jul 08 2024 04:34:34

%S 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,

%T 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,

%U 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,3,3,3,3,3,3,3,3,3,3

%N Number of semiprime triples <= n.

%C A semiprime triple is <= n if its least member is <= n;

%C if a(n-1)<a(n) then (n,n+1,n+2) is a semiprime triple, A086005(a(n))=n+1.

%Y Cf. A001358, A056809, A086005.

%K nonn

%O 1,85

%A _Reinhard Zumkeller_, Jul 07 2003