login
Greatest number less than n such that the number of prime factors is one less than that of n; a(1)=0.
0

%I #3 Mar 30 2012 18:50:38

%S 0,1,1,3,1,5,1,6,7,7,1,10,1,13,13,12,1,15,1,15,19,19,1,20,23,23,26,26,

%T 1,26,1,24,31,31,31,30,1,37,37,30,1,39,1,39,39,43,1,40,47,49,47,51,1,

%U 52,53,52,53,53,1,52,1,61,62,48,61,65,1,65,67,69,1,60,1,73,74,74,73

%N Greatest number less than n such that the number of prime factors is one less than that of n; a(1)=0.

%C A001222(a(n)) = A001222(n) - 1 for n>1.

%Y Cf. A079890.

%K nonn

%O 1,4

%A _Reinhard Zumkeller_, Oct 26 2003