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A347121
a(n) = A347136(n) - 2*n.
3
-1, 1, 2, 11, 2, 28, 4, 49, 31, 40, 2, 128, 4, 62, 66, 179, 2, 209, 4, 188, 102, 76, 6, 472, 59, 98, 218, 286, 2, 420, 6, 601, 126, 112, 146, 859, 4, 134, 162, 700, 2, 636, 4, 368, 498, 168, 6, 1592, 149, 445, 186, 466, 6, 1252, 178, 1058, 222, 184, 2, 1704, 6, 216, 756, 1931, 230, 828, 4, 548, 278, 940, 2, 3041, 6
OFFSET
1,3
FORMULA
a(n) = A347136(n) - 2*n.
a(A000040(n)) = A001223(n).
PROG
(PARI)
A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A347121(n) = (sumdiv(n, d, d*A003961(n/d))-(2*n));
CROSSREFS
Cf. A000040, A001223, A003961, A347136, A347122 (Möbius transform).
Cf. also A341512, A346239, A347236.
Sequence in context: A224480 A037299 A329941 * A341512 A276676 A077805
KEYWORD
sign
AUTHOR
Antti Karttunen, Aug 24 2021
STATUS
approved