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%I #50 Aug 25 2014 18:34:36
%S 0,0,-2,0,-4,0,-6,-6,1,9,-1,9,-3,-3,-5,9,-7,18,0,0,-2,18,-4,-2,-6,-6,
%T 1,27,-1,27,-3,-3,-5,-3,-7,36,0,0,-2,36,-4,36,-6,-6,1,45,-1,3,-3,-3,
%U -5,45,-7,4,0,0,-2,54,-4,54,-6,-6,1,3,-1,63,-3,-3,-5,63
%N Difference between least prime factor of n and the digital root of n.
%H Jens Kruse Andersen, <a href="/A245075/b245075.txt">Table of n, a(n) for n = 2..10000</a>
%e n least prime root(n) difference
%e 2 2 2 0
%e 3 3 3 0
%e 4 2 4 -2
%e 5 5 5 0
%e 6 2 6 -4
%e 7 7 7 0
%e 8 2 8 -6
%e 9 3 9 -6
%e 10 2 1 1
%o (PARI) a(n)=factor(n)[1,1]-(n-1)%9-1
%o vector(100, n, a(n+1)) \\ _Jens Kruse Andersen_, Aug 23 2014
%Y Cf. A020639, A010888.
%K easy,sign,base
%O 2,3
%A _Odimar Fabeny_, Aug 21 2014
%E Multiple corrections by _Jens Kruse Andersen_, Aug 23 2014
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