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Number of solutions 1<=x<=m to gcd(m,x) = tau(m) where m = A033950(n).
0

%I #9 Jul 06 2024 01:30:09

%S 1,1,1,2,1,2,2,2,4,6,4,2,4,6,10,4,12,6,8,10,16,18,12,4,22,16,20,18,28,

%T 4,30,6,22,8,36,40,42,28,8,30,46,8,10,52,42,36,16,20,12,58,8,60,40,12,

%U 42,66,12,46,70,72,20,16,100,78,52,16,82,12,18,58,88,8,60,96,20,66,100

%N Number of solutions 1<=x<=m to gcd(m,x) = tau(m) where m = A033950(n).

%o (PARI) for(n=1,1000,if(sum(i=1,n,if(gcd(n,i)-numdiv(n),0,1))>0,print1(sum(i=1,n,if(gcd(n,i)-numdiv(n),0,1)),",")))

%Y Cf. A033950.

%K easy,nonn

%O 1,4

%A _Benoit Cloitre_, Jun 10 2002

%E Name corrected by _Sean A. Irvine_, Jul 05 2024