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Smallest prime factors of zerofull restricted pandigital numbers.
3

%I #8 May 13 2013 01:49:23

%S 3,2,3,3,2,3,3,2,3,2,2,2,3,3,3,2,3,2,2,3,2,2,3,2,3,2,3,3,2,3,3,2,3,3,

%T 2,3,3,3,3,3,3,3,2,3,2,3,3,3,3,2,3,2,2,2,3,2,3,3,2,3,3,2,3,3,2,3,2,2,

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

%N Smallest prime factors of zerofull restricted pandigital numbers.

%C a(n) = A020639(A050278(n)); 2 <= a(n) <= 3.

%C a(n) is 2 1653120 times and 3 1612800 times, making the average value 202/81 = 2.493.... [_Charles R Greathouse IV_, Sep 09 2011]

%F a(n) = 2 + A000035(A050278(n)).

%e A050278(1)=1023456789=3*3*3*3*2221*5689 --> a(1)=3;

%e A050278(10)=1023457896=2*2*2*3*3*3*59*80309 --> a(10)=2;

%e A050278(100)=1023495786=2*3*3*739*76943 --> a(100)=2;

%e A050278(1000)=1024658793=3*3*113850977 --> a(1000)=3.

%K fini,nonn,base

%O 1,1

%A _Reinhard Zumkeller_, Jun 11 2010

%E Edited by _Charles R Greathouse IV_, Aug 02 2010