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%I #12 Apr 26 2017 02:48:26
%S 1,1,2,1,2,1,2,1,2,1,2,1,3,1,2,2,3,1,2,2,3,2,3,2,3,1,2,2,2,2,3,2,3,2,
%T 2,2,3,2,2,1,2,2,3,3,2,2,4,1,2,2,2,3,3,2,3,2,3,2,2,1,2,2,2,2,2,1,3,2,
%U 2,2,2,1,4,1,2,2,3,2,2,2,2,2,4,1,2,2,3,2,3,2,3,3,3,1,2,1,3,1,3,3,2,2,3,2,3
%N Number of distinct prime factors of n*rad(n)+1, where rad=A007947 (squarefree kernel).
%C a(n)=A001221(A078310(n)).
%H Reinhard Zumkeller, <a href="/A078313/b078313.txt">Table of n, a(n) for n = 1..10000</a>
%t A078313[n_] := PrimeNu[n*Times @@ FactorInteger[n][[All, 1]] + 1]; Array[A078313, 50] (* _G. C. Greubel_, Apr 25 2017 *)
%o (PARI) a(n)=omega(n*vecprod(factor(n)[,1])+1) \\ _Charles R Greathouse IV_, Jul 09 2013
%o (Haskell)
%o a078313 = a001221 . a078310 -- _Reinhard Zumkeller_, Jul 23 2013
%Y Cf. A078314, A078315.
%K nonn
%O 1,3
%A _Reinhard Zumkeller_, Nov 23 2002
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