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%I #4 Oct 15 2013 22:32:25
%S 1,0,0,2,0,1,0,6,6,-6,0,-2,0,-4,-2,5,0,4,0,-5,-7,0,0,1,2,2,6,1,0,-7,0,
%T 3,1,-3,-4,4,0,-1,5,-3,0,-6,0,4,1,3,0,7,6,-2,-5,1,0,4,3,2,-1,0,0,-4,0,
%U 2,-1,8,2,5,0,4,7,-7,0,4,0,-1,4,1,5,6,0,1,6,3,0,0,0,5,1,12,0,-1,-1,4,5,0,-1,10,0,8,13,-6,0,-10,0,-1,-9,-3,0,4,0,-7,-10
%N Sum of digits of n minus the sum of digits of all distinct prime factors of n.
%F a[n]=A007953[n]-A095402[n]
%e n=1000: A007953[1000]=1, prime set={2,5}, A095402[1000]=7, a[1000]=1-7=-6
%t ffi[x_] :=Flatten[FactorInteger[x]] lf[x_] :=Length[FactorInteger[x]] ba[x_] :=Table[Part[ffi[x], 2*j-1], {j, 1, lf[x]}] sd[x_] :=Apply[Plus, IntegerDigits[x]] tdp[x_] :=Flatten[Table[IntegerDigits[Part[ba[x], j]], {j, 1, lf[x]}], 1] sdp[x_] :=Apply[Plus, tdp[x]] a=Table[sd[w], {w, 1, 150}];b=Table[sdp[w], {w, 1, 150}];b-a
%Y Cf. A007953, A051351.
%K base,sign
%O 1,4
%A _Labos Elemer_, Jun 21 2004
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