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A353805
a(n) = A051027(n) / gcd(A051027(n), A353802(n)), where A051027(n) = sigma(sigma(n)), and A353802(n) = Product_{p^e||n} sigma(sigma(p^e)).
7
1, 1, 1, 1, 1, 1, 1, 1, 1, 13, 1, 1, 1, 1, 5, 1, 1, 1, 1, 1, 3, 13, 1, 1, 1, 1, 1, 1, 1, 65, 1, 1, 31, 10, 31, 1, 1, 1, 5, 13, 1, 3, 1, 1, 1, 13, 1, 1, 1, 1, 5, 57, 1, 1, 65, 1, 31, 13, 1, 5, 1, 1, 1, 1, 7, 403, 1, 1, 3, 403, 1, 1, 1, 1, 1, 1, 3, 5, 1, 1, 1, 13, 1, 3, 70, 1, 5, 13, 1, 13, 31, 1, 85, 13, 5, 1, 1, 13
OFFSET
1,10
COMMENTS
Denominator of fraction A353802(n) / A051027(n).
FORMULA
a(n) = A051027(n) / A353804(n).
PROG
(PARI)
A051027(n) = sigma(sigma(n));
A353805(n) = { my(f = factor(n)); (A051027(n) / gcd(A051027(n), prod(k=1, #f~, A051027(f[k, 1]^f[k, 2])))); };
CROSSREFS
Cf. A000203, A051027, A353802, A353803, A353804, A353806 (numerators).
Positions of 1's is given by the union of A336547 and A353807.
Cf. also A353755, A353756.
Sequence in context: A367303 A357912 A251072 * A332018 A010227 A010228
KEYWORD
nonn,frac
AUTHOR
Antti Karttunen, May 08 2022
STATUS
approved