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Partial sums of A229110, where A229110(n) = antisigma(n) mod n = A024816(n) mod n.
2

%I #8 Jul 05 2024 12:30:13

%S 0,0,2,5,9,12,18,23,28,35,45,47,59,70,76,85,101,107,125,133,143,162,

%T 184,184,203,226,240,254,282,285,315,332,350,381,403,438,474,509,531,

%U 541,581,590,632,658,670,713,759,803,844,876,906,938,990,1005,1043,1063

%N Partial sums of A229110, where A229110(n) = antisigma(n) mod n = A024816(n) mod n.

%C Antisigma(n) = A024816(n) = sum of non-divisors of n.

%C See A239877 - values of n for which a(n) / n is integer.

%H Jaroslav Krizek, <a href="/A239876/b239876.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = Sum_{k = 1...n} antisigma(k) mod k = Sum_{k = 1...n} A229110(k).

%F a(n) = a(n-1) for numbers n from A159907 if there are no odd multiply perfect numbers (A007691).

%t Accumulate[Table[Mod[Total[Complement[Range[n],Divisors[n]]],n],{n,60}]] (* _Harvey P. Dale_, Jul 05 2024 *)

%o (Magma)[&+[(k*(k+1)div 2 - SumOfDivisors (k)) mod k: k in [1..n]]: n in [1..1000]]

%Y Cf. A024816, A229110, A239877.

%K nonn

%O 1,3

%A _Jaroslav Krizek_, Mar 29 2014