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A344999
a(n) = A048250(n) * A345001(n).
6
-1, 0, -4, 9, -18, 60, -40, 33, 4, 90, -108, 240, -154, 120, 48, 93, -270, 288, -340, 468, 0, 180, -504, 672, -54, 210, 52, 768, -810, 3096, -928, 237, -192, 270, -480, 948, -1330, 300, -336, 1404, -1638, 5088, -1804, 1584, 648, 360, -2160, 1680, -216, 684, -720, 2100, -2754, 1116, -1584, 2400, -960, 450, -3420, 10080
OFFSET
1,3
FORMULA
a(n) = A048250(n) * A345001(n).
a(n) = A344998(n) - A345043(n).
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A048250(n) = factorback(apply(p -> p+1, factor(n)[, 1]));
A345001(n) = (sigma(n)+A003415(n)-(2*n));
A344999(n) = (A048250(n) * A345001(n));
CROSSREFS
Cf. A345003 [gives k for which a(k) = A344998(k)], A345004, A345005.
Sequence in context: A015713 A049198 A146303 * A203205 A330375 A147977
KEYWORD
sign
AUTHOR
Antti Karttunen, Jun 05 2021
STATUS
approved