A326044 a(n) = n - {the largest square dividing its sum of divisors}: a(n) = n - A008833(sigma(n)).

0, 1, -1, 3, 4, 2, 3, 7, 8, 1, 7, 8, 12, 10, 11, 15, 8, 17, 15, 19, 5, -14, 19, 20, 24, 25, 23, 24, 28, -6, 15, 23, 17, 25, 19, 35, 36, 34, 35, 31, 40, 26, 39, 40, 44, 10, 31, 44, 48, 49, 15, 3, 44, 50, 19, 52, 41, 49, 55, 56, 60, 46, 59, 63, 61, -78, 63, 59, 53, -74, 35, 71, 72, 73, 71, 72, 61, 74, 63, 79, -40

Offset

1,4

Links

Antti Karttunen, Table of n, a(n) for n = 1..20000

Index entries for sequences related to sigma(n)

Formula

a(n) = n - A326039(n) = n - A008833(A000203(n)).

a(n) = A033879(n) + A326045(n).

Prog

(PARI)
A008833(n) = (n/core(n));
A326039(n) = A008833(sigma(n));
A326044(n) = (n-A326039(n));

Crossrefs

Cf. A000203, A008833, A033879, A326039, A326045, A326046.

Sequence in context: A271590 A232115 A275529 * A011414 A155746 A243111

Adjacent sequences: A326041 A326042 A326043 * A326045 A326046 A326047

Keyword

sign

Author

Antti Karttunen, Jun 05 2019

Status

approved