A344731
Numbers k such that k divides A306069(k).
Original entry on oeis.org
1, 275, 277, 3337, 3353, 3359, 39675, 39689, 472467, 797806459, 9501109507
Offset: 1
a(1) = 1 since A306069(1) = 1 is divisible by 1.
a(2) = 275 since A306069(275) = 1375 = 5 * 275 is divisible by 275.
-
f[p_, e_] := If[Mod[e, 2] == 1, (e + 1), e]; s[1] = 1; s[n_] := s[n] = s[n - 1] + Times @@ f @@@ FactorInteger[n]; Select[Range[40000], Divisible[s[#], #] &]
A344732
Numbers k such that k divides Sum_{j=1..k} A048105(j).
Original entry on oeis.org
1, 2, 3, 54, 58, 62, 71, 10535, 10541, 10579, 135242, 135243, 1733777, 1733781, 1733895, 1733905, 1733999, 22216757, 22216765, 22216790, 22216808, 22216814, 46745561148, 46745561156
Offset: 1
a(1) = 1 since A048105(1) = 0 is divisible by 1.
a(4) = 54 since Sum_{j=1..54} A048105(j) = 54 is divisible by 54.
The non-unitary version of
A050226.
-
s[1] = 0; s[n_] := s[n] = s[n - 1] + DivisorSigma[0, n] - 2^PrimeNu[n]; Select[Range[140000], Divisible[s[#], #] &]
Showing 1-2 of 2 results.
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