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A192895
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A000120-deficiency of n.
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18
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-1, 0, -1, 1, -1, 2, -2, 2, 1, 2, -2, 5, -2, 2, 1, 3, -1, 6, -2, 5, 3, 2, -3, 8, 0, 2, 1, 6, -3, 10, -4, 4, 4, 2, 3, 11, -2, 2, 2, 8, -2, 12, -3, 6, 7, 2, -4, 11, 1, 6, 1, 6, -3, 10, 1, 10, 2, 2, -4, 19, -4, 2, 5, 5, 4, 12, -2, 5, 4, 12, -3, 16, -2, 2, 8, 6
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OFFSET
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1,6
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LINKS
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FORMULA
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a(n) = Sum(A000120(d): 1 <= d < n and n mod d = 0) - A000120(n); see A175522 for motivation and more information;
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MATHEMATICA
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a[n_] := DivisorSum[n, Total[IntegerDigits[#, 2]]*(-1)^Boole[# == n]&]; Array[a, 80] (* Jean-François Alcover, Dec 05 2015, adapted from PARI *)
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PROG
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(Haskell)
a192895 n =
sum (map a000120 $ filter ((== 0) . (mod n)) [1..n-1]) - a000120 n
a192895_list = map a192895 [1..]
(Python)
from sympy import divisors
def A192895(n): return sum((d.bit_count() if d<n else -d.bit_count()) for d in divisors(n, generator=True)) # Chai Wah Wu, Jul 25 2023
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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