%I #12 Apr 30 2022 09:15:11
%S 1,1,2,3,4,4,5,5,5,5,6,6,7,7,8,9,10,10,11,11,12,12,13,13,14,14,15,15,
%T 16,16,17,17,18,18,19,19,20,20,21,21,22,22,23,23,23,23,24,24,25,25,26,
%U 26,27,27,28,28,29,29,30,30,31,31,31,32,33,33,34,34,35,35,36,36,37,37
%N a(n) = Card( k, 0<k<=n such that k is relatively prime to tau(k)=A000005(k)).
%H Michael De Vlieger, <a href="/A070546/b070546.txt">Table of n, a(n) for n = 1..10000</a>
%t Accumulate[Table[Boole[CoprimeQ[n, DivisorSigma[0, n]]], {n, 1, 100}]] (* _Amiram Eldar_, Apr 30 2022 *)
%o (PARI) for(n=1,100,print1(sum(i=1,n,if(gcd(i,numdiv(i))-1,0,1)),","))
%Y Partial sums of A322980.
%Y Cf. A000005, A009191, A046642.
%K easy,nonn
%O 1,3
%A _Benoit Cloitre_, May 02 2002
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