A326068 - OEIS

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A326068

a(n) = n - sigma(A032742(n)), where sigma is the sum of divisors of n and A032742 gives the largest proper divisor of n.

0, 1, 2, 1, 4, 2, 6, 1, 5, 4, 10, 0, 12, 6, 9, 1, 16, 5, 18, 2, 13, 10, 22, -4, 19, 12, 14, 4, 28, 6, 30, 1, 21, 16, 27, -3, 36, 18, 25, -2, 40, 10, 42, 8, 21, 22, 46, -12, 41, 19, 33, 10, 52, 14, 43, 0, 37, 28, 58, -12, 60, 30, 31, 1, 51, 18, 66, 14, 45, 22, 70, -19, 72, 36, 44, 16, 65, 22, 78, -10, 41, 40, 82, -12, 67, 42, 57, 4, 88, 12

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,3

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..16384

Index entries for sequences related to sigma(n)

FORMULA

a(n) = n - A326065(n) = n - A000203(A032742(n)).

a(n) = A326067(n) + A033879(n).

PROG

(PARI)

A032742(n) = if(1==n, n, n/vecmin(factor(n)[, 1]));