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A296081
a(n) = gcd(tau(n)-1, sigma(n)-1), where tau = A000005 and sigma = A000203.
3
0, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 3, 5, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 2, 1, 1, 1, 1, 7, 1, 7, 1, 1, 1, 1, 1, 1, 1, 6, 1, 1, 1, 5, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 5, 5, 8, 1, 1, 1, 1, 1
OFFSET
1,4
LINKS
FORMULA
a(n) = gcd(A032741(n), A039653(n)).
a(n) = gcd(A039653(n), A065608(n)).
MATHEMATICA
Array[GCD[DivisorSigma[0, #]-1, DivisorSigma[1, #]-1]&, 120] (* Harvey P. Dale, Oct 18 2022 *)
PROG
(Scheme) (define (A296081 n) (gcd (A039653 n) (A032741 n)))
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 05 2017
STATUS
approved