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Numbers of prime factors of k, k defined in A117078.
1

%I #6 Mar 31 2012 14:42:50

%S 0,0,1,0,1,2,1,1,1,1,2,1,1,1,1,1,1,1,1,1,1,1,1,2,1,1,2,1,1,2,1,2,1,1,

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

%N Numbers of prime factors of k, k defined in A117078.

%C a(n) = 0 only for n = 1, 2 and 4.

%H Remi Eismann, <a href="/A106752/b106752.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = numbers of factors of A117078(n). A117078(n) : smallest k such that prime(n+1) = prime(n) + (prime(n) mod k), or 0 if no such k exists.

%e For a(1), k=0 thus a(1)=0,

%e For a(3), k=3 thus a(3)=1,

%e For a(11), k=25=5*5 thus a(11)=2.

%Y Cf. A117078, A117563, A118534, A118144, A118123.

%K nonn

%O 1,6

%A _RĂ©mi Eismann_, Jun 22 2007, Feb 14 2008