A325976 - OEIS

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A325976

a(n) is the largest k <= n such that k and (2n-sigma(n)) [= A033879(n)] are relatively prime.

1, 2, 3, 4, 5, 1, 7, 8, 9, 9, 11, 11, 13, 13, 13, 16, 17, 17, 19, 19, 21, 21, 23, 23, 25, 23, 27, 1, 29, 29, 31, 32, 31, 33, 35, 36, 37, 37, 39, 39, 41, 41, 43, 43, 43, 43, 47, 47, 49, 50, 49, 49, 53, 53, 55, 55, 57, 57, 59, 59, 61, 61, 63, 64, 65, 65, 67, 67, 67, 69, 71, 71, 73, 73, 75, 73, 77, 77, 79, 79, 81, 81, 83, 83, 85, 83

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OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..16385

Antti Karttunen, Data supplement: n, a(n) computed for n = 1..65537

Index entries for sequences related to sigma(n)

FORMULA

a(n) = n - A325817(n) = A033879(n) + A325826(n).

a(n) >= A325959(n).

gcd(a(n), A325826(n)) = 1.

PROG