Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #11 Jun 30 2021 10:33:53
%S 1,1,2,1,1,1,3,2,1,1,8,1,1,1,4,1,7,1,12,1,1,1,11,2,1,3,16,1,1,1,5,1,1,
%T 1,2,1,1,1,17,1,1,1,24,13,1,1,14,2,9,1,28,1,9,1,23,1,1,1,46,1,1,17,6,
%U 1,1,1,36,1,1,1,13,1,1,11,40,1,1,1,22,4,1,1,62,1,1,1,35,1,41,1,48,1,1,1,17,1,11,25
%N a(n) = A003415(n) / gcd(A003415(n), A069359(n)).
%H Antti Karttunen, <a href="/A344756/b344756.txt">Table of n, a(n) for n = 2..12012</a>
%H Antti Karttunen, <a href="/A344756/a344756.txt">Data supplement: n, a(n) computed for n = 2..65537</a>
%F a(n) = A003415(n) / A340070(n) = A003415(n) / gcd(A003415(n), A069359(n)).
%o (PARI)
%o A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
%o A069359(n) = (n*sumdiv(n, d, isprime(d)/d)); \\ From A069359
%o A344756(n) = { my(u=A003415(n)); (u/gcd(u,A069359(n))); };
%Y Cf. A003415, A005117 (for n > 1 gives the positions of ones), A069359, A340070, A344757.
%Y Cf. also A344696.
%K nonn
%O 2,3
%A _Antti Karttunen_, May 28 2021