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Numbers of prime factors of l, where l is defined in A118534.
2

%I #8 Jul 29 2012 11:32:58

%S 0,0,1,0,2,2,2,2,1,3,2,2,2,2,1,1,2,2,3,2,1,3,2,4,2,3,3,3,3,3,2,3,4,2,

%T 3,2,1,2,2,1,2,3,4,4,3,2,1,2,4,4,1,2

%N Numbers of prime factors of l, where l is defined in A118534.

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

%H Remi Eismann, <a href="/A118144/b118144.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = numbers of factors of l, largest l such that prime(n+1) = prime(n) + (prime(n) mod l), or 0 if no such l exists.

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

%e for a(3), l=3 thus a(3)=1,

%e for a(8), l=15=3*5 thus a(8)=2,

%e for a(24), l=81=3*3*3*3 thus a(24)=4.

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

%K nonn

%O 1,5

%A _RĂ©mi Eismann_ and _Fabien Sibenaler_, May 14 2006, Feb 14 2008