OFFSET
1,2
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..16384
FORMULA
EXAMPLE
For n = 6; divisors d of 6: {1, 2, 3, 6}; sigma(d): {1, 3, 4, 12}; lcm_{d|6} sigma(d) = 12; a(6) = 12/1 + 12/3 + 12/4 + 12/12 = 20.
MATHEMATICA
a[n_] := LCM @@ DivisorSigma[1, Divisors[n]] * DivisorSum[n, 1/DivisorSigma[1, #] &]; Array[a, 100] (* Amiram Eldar, Dec 09 2022 *)
PROG
(Magma) [&+[1/SumOfDivisors(d): d in Divisors(n)] * LCM([SumOfDivisors(d): d in Divisors(n)]): n in [1..100]]
(PARI)
A069934(n) = my(d = divisors(n)); lcm(vector(#d, k, sigma(d[k])));
CROSSREFS
KEYWORD
nonn,mult
AUTHOR
Jaroslav Krizek, Dec 24 2015
STATUS
approved