Numbers m = Sum_{k=1..n} sigma(k)/k such that Sum_{k=1..n} sigma(k)/k is an integer for any k.
A168132
Numbers m = Sum_{k=1..n} sigma(k)/k such that Sum_{k=1..n} sigma(k)/k is an integer for any k.
Terms
- a(0) =1a(1) =2a(2) =7a(3) =9a(4) =14a(5) =52a(6) =149a(7) =213a(8) =673a(9) =1778a(10) =3653a(11) =6831a(12) =9868a(13) =570972a(14) =2835107a(15) =3613594a(16) =47211979a(17) =60418265a(18) =99909506a(19) =1701207282a(20) =4587170542a(21) =10955668024a(22) =29031152874a(23) =114018751785a(24) =813149731047
External references
- oeis: A168132