|
%I #14 Jun 07 2021 06:50:32
%S 81,3375,15625,231525,713097,1058841,1500625,4348377,5764801,16891497,
%T 163555875,209548647,239010993,239160735,254205875,267651475,
%U 405189675,451699875,958403475,1050284375,1213014231,1501534375,1695809375,1809323971,1942143291
%N Odd numbers whose arithmetic derivative (A003415) is equal to Dedekind psi (A001615) applied to the same number.
%C Conjectured to be also the odd numbers k for which A344998(k) = A344999(k).
%o (PARI)
%o A001615(n) = if(1==n,n, my(f=factor(n)); prod(i=1, #f~, f[i, 1]^f[i, 2] + f[i, 1]^(f[i, 2]-1))); \\ After code in A001615
%o A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
%o isA345005(n) = ((n%2)&&(A003415(n)==A001615(n)));
%Y Odd terms in A301939, but see also A345003.
%Y Cf. A001615, A003415, A344998, A344999.
%K nonn,more
%O 1,1
%A _Antti Karttunen_, Jun 05 2021
|
