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A353785
a(n) = A353783(n) / A080398(n).
2
1, 1, 2, 1, 1, 2, 4, 1, 1, 1, 2, 2, 1, 4, 2, 1, 3, 1, 2, 1, 4, 2, 4, 2, 1, 1, 4, 4, 1, 2, 16, 3, 2, 3, 4, 1, 1, 2, 2, 1, 1, 4, 2, 2, 1, 4, 8, 2, 1, 1, 6, 1, 9, 4, 2, 4, 2, 1, 2, 2, 1, 16, 4, 1, 1, 2, 2, 3, 4, 4, 12, 1, 1, 1, 2, 2, 4, 2, 8, 1, 11, 1, 2, 4, 3, 2, 2, 2, 3, 1, 4, 4, 16, 8, 2, 6, 7, 1, 2, 1, 1, 6, 4, 1, 4
OFFSET
1,3
FORMULA
a(n) = A353783(n) / A080398(n).
MATHEMATICA
Array[Apply[LCM, DivisorSigma[1, Power @@@ FactorInteger[#]]]/Apply[Times, FactorInteger[DivisorSigma[1, #]][[All, 1]]] &, 105] (* Michael De Vlieger, May 08 2022 *)
PROG
(PARI)
A080398(n) = factorback(factor(sigma(n))[, 1]);
A353783(n) = { my(f=factor(n)~); lcm(vector(#f, i, sigma(f[1, i]^f[2, i]))); };
A353785(n) = (A353783(n) / A080398(n));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 08 2022
STATUS
approved