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A318678
Sum of deficiencies of deficient divisors of n.
3
1, 2, 3, 3, 5, 4, 7, 4, 8, 8, 11, 5, 13, 12, 13, 5, 17, 9, 19, 9, 19, 20, 23, 6, 24, 24, 22, 13, 29, 16, 31, 6, 31, 32, 33, 10, 37, 36, 37, 10, 41, 24, 43, 25, 30, 44, 47, 7, 48, 34, 49, 31, 53, 23, 53, 14, 55, 56, 59, 17, 61, 60, 46, 7, 63, 40, 67, 43, 67, 40, 71, 11, 73, 72, 58, 49, 75, 48, 79, 11, 63, 80, 83, 25, 83, 84, 85, 26, 89, 33, 89, 61
OFFSET
1,2
FORMULA
a(n) = Sum_{d|n} [A033879(d) > 0]*A033879(d).
a(n) = A296075(n) + A318679(n).
MATHEMATICA
f[n_] := 2 n - DivisorSigma[1, n]; Array[DivisorSum[#, f, f@ # >= 0 &] &, 92] (* Michael De Vlieger, Sep 04 2018 *)
PROG
(PARI) A318678(n) = sumdiv(n, d, d=d+d-sigma(d); (d>0)*d);
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 04 2018
STATUS
approved