A239877 - OEIS

%I #13 Sep 08 2022 08:46:07

%S 1,2,6,14,23,93,95,343,1924,13358,27385,54709,150554,445242,581211,

%T 589819,14733535,18859421,19861702,371619757,775908129,1076759948,

%U 1083679128,7402437933,42679464436

%N Numbers k that divide A239876(k).

%C Values of k for which A239876(k) / k is an integer.

%C A239876 = partial sums of A229110 where A229110(n) = antisigma(n) mod n = A024816(n) mod n.

%C a(26) > 3*10^11. - _Giovanni Resta_, Mar 29 2014

%e a(4) = 14 is in the sequence because A239876(14) / 14 = 70 / 14 = 5 is an integer.

%o (Magma) [n: n in [1..1000] | u eq 0 where u is ((&+[(k*(k+1)div 2 - SumOfDivisors (k)) mod k: k in [1..n]]) mod n)]

%Y Cf. A024816, A229110, A239876.

%K nonn

%O 1,2

%A _Jaroslav Krizek_, Mar 29 2014

%E a(13)-a(25) from _Giovanni Resta_, Mar 29 2014