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A336852
a(n) = sigma(A003961(n)) - sigma(n).
7
0, 1, 2, 6, 2, 12, 4, 25, 18, 14, 2, 50, 4, 24, 24, 90, 2, 85, 4, 62, 40, 20, 6, 180, 26, 30, 116, 100, 2, 120, 6, 301, 36, 26, 48, 312, 4, 36, 52, 230, 2, 192, 4, 98, 170, 48, 6, 602, 76, 135, 48, 136, 6, 504, 40, 360, 64, 38, 2, 456, 6, 56, 268, 966, 60, 192, 4, 134, 84, 240, 2, 1045, 6, 54, 218, 172, 72, 264, 4, 782
OFFSET
1,3
COMMENTS
Inverse Möbius transform of A336853(n) = (A003961(n) - n).
FORMULA
a(n) = Sum_{d|n} (A003961(d)-d).
a(n) = A003973(n) - A000203(n) = A000203(A003961(n)) - A000203(n).
a(n) = A336851(n) + A286385(n).
PROG
(PARI)
A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A336852(n) = (sigma(A003961(n)) - sigma(n));
(PARI) A336852(n) = sumdiv(n, d, A003961(d)-d);
CROSSREFS
Cf. A001105 (positions of odd terms), A001359 (positions of 2's).
Sequence in context: A319048 A066900 A356016 * A079462 A189218 A122663
KEYWORD
nonn
AUTHOR
Antti Karttunen, Aug 05 2020
STATUS
approved