A380463 Third coefficient of the lindep transform of the sum of squarefree divisors of n, A048250.

0, -1, -1, 1, -1, 0, -1, 2, 1, 2, -1, 0, -1, 4, -3, -3, -1, 0, -1, 2, -1, 2, -1, 0, 1, -6, -4, 4, -1, 6, -1, -3, 3, -6, -4, 0, -1, -6, 5, 4, -1, 6, -1, -4, -3, -6, -1, 0, 1, -4, -3, -2, -1, 6, 4, 0, -1, -6, -1, 0, -1, -6, -1, -3, 8, -12, -1, 2, 3, -4, -1, 0, -1, -6, 3, 4, 1, -12, -1, 8, -4, -6, -1, 0, -7, -6, 9, -4, -1, 0, 7, 8, -12, -6, -5, 0

Offset

1,8

Comments

See A339792 for a definition of lindep-transform.

Links

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

Formula

a(n) = -(A048250(n)*A380461(n) + n*A380462(n)).

Prog

(PARI)
A048250(n) = factorback(apply(p -> p+1, factor(n)[, 1]));
A380463(n) = { my(v=lindep([A048250(n), n, 1])); (v*sign(v[1]))[3]; };

Crossrefs

Cf. A048250, A380461, A380462.

Cf. also A339792, A380473, A380483.

Sequence in context: A165579 A130911 A319300 * A118829 A118832 A122807

Adjacent sequences: A380460 A380461 A380462 * A380464 A380465 A380466

Keyword

sign

Author

Antti Karttunen, Jan 26 2025

Status

approved