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%I #18 Nov 06 2014 15:35:19
%S 0,0,1,1,4,1,8,6,9,5,22,8,28,15,19,20,51,20,64,30,39,33,98,33,83,56,
%T 89,55,151,46,167,95,107,95,150,71,233,120,172,106,297,92,325,163,186,
%U 162,403,144,358,189,279,217,505,173,375,230,342,276,635,165,645,338
%N a(n) = sum of all the remainders when n is divided by positive integers less than and coprime to n.
%H Charles R Greathouse IV, <a href="/A067439/b067439.txt">Table of n, a(n) for n = 1..10000</a>
%e a(8) = 6. The remainders when 8 is divided by the coprime numbers 1, 3, 5 and 7 are 0, 2, 3 and 1, whose sum = 6.
%t a[n_] := Sum[If[GCD[i, n]>1, 0, Mod[n, i]], {i, 1, n-1}]
%t Table[Total[Mod[n,#]&/@Select[Range[n-1],CoprimeQ[#,n]&]],{n,70}] (* _Harvey P. Dale_, May 22 2012 *)
%o (PARI) a(n)=sum(i=1,n-1,if(gcd(n,i)==1,n%i)) \\ _Charles R Greathouse IV_, Jul 17 2012
%Y Cf. A004125, A067435, A067436, A024934, A033955.
%K nonn
%O 1,5
%A _Amarnath Murthy_, Jan 29 2002
%E Edited by _Dean Hickerson_, Feb 15 2002