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A239876
Partial sums of A229110, where A229110(n) = antisigma(n) mod n = A024816(n) mod n.
2
0, 0, 2, 5, 9, 12, 18, 23, 28, 35, 45, 47, 59, 70, 76, 85, 101, 107, 125, 133, 143, 162, 184, 184, 203, 226, 240, 254, 282, 285, 315, 332, 350, 381, 403, 438, 474, 509, 531, 541, 581, 590, 632, 658, 670, 713, 759, 803, 844, 876, 906, 938, 990, 1005, 1043, 1063
OFFSET
1,3
COMMENTS
Antisigma(n) = A024816(n) = sum of non-divisors of n.
See A239877 - values of n for which a(n) / n is integer.
LINKS
FORMULA
a(n) = Sum_{k = 1...n} antisigma(k) mod k = Sum_{k = 1...n} A229110(k).
a(n) = a(n-1) for numbers n from A159907 if there are no odd multiply perfect numbers (A007691).
MATHEMATICA
Accumulate[Table[Mod[Total[Complement[Range[n], Divisors[n]]], n], {n, 60}]] (* Harvey P. Dale, Jul 05 2024 *)
PROG
(Magma)[&+[(k*(k+1)div 2 - SumOfDivisors (k)) mod k: k in [1..n]]: n in [1..1000]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Mar 29 2014
STATUS
approved