login
A294649
a(n) = numerator(A206369(n))/n.
3
1, 1, 2, 3, 4, 1, 6, 5, 7, 2, 10, 1, 12, 3, 8, 11, 16, 7, 18, 3, 4, 5, 22, 5, 21, 6, 20, 9, 28, 4, 30, 21, 20, 8, 24, 7, 36, 9, 8, 1, 40, 2, 42, 15, 28, 11, 46, 11, 43, 21, 32, 9, 52, 10, 8, 15, 12, 14, 58, 2, 60, 15, 2, 43, 48, 10, 66, 12, 44, 12, 70, 35, 72, 18, 14
OFFSET
1,3
COMMENTS
a(n) = 1 for n in A127724.
LINKS
László Tóth, A survey of the alternating sum-of-divisors function, arXiv:1111.4842 [math.NT], 2011-2014.
MATHEMATICA
(* b = A209369 *) b[n_] := n*DivisorSum[n, LiouvilleLambda[#]/# &];
a[n_] := Numerator[b[n]/n];
Array[a, 100] (* Jean-François Alcover, Dec 04 2017 *)
PROG
(PARI) rhope(p, e) = my(s=1); for(i=1, e, s=s*p + (-1)^i); s;
rho(n) = my(f=factor(n)); prod(i=1, #f~, rhope(f[i, 1], f[i, 2]));
a(n) = numerator(rho(n)/n);
CROSSREFS
Cf. A127724 (k-imperfect), A206369, A294650 (denominator).
A225679 is a subsequence (on squarefree indices). - Michel Marcus, Dec 22 2017
Sequence in context: A330342 A065338 A316272 * A350778 A001438 A342410
KEYWORD
nonn,frac
AUTHOR
Michel Marcus, Nov 06 2017
STATUS
approved