Numbers k for which A003958(sigma(k)) = 2*A003958(k), where A003958 is multiplicative with a(p^e) = (p-1)^e and sigma is the sum of divisors function.
A351447
Numbers k for which A003958(sigma(k)) = 2*A003958(k), where A003958 is multiplicative with a(p^e) = (p-1)^e and sigma is the sum of divisors function.
Terms
- a(0) =2a(1) =98a(2) =120a(3) =136a(4) =312a(5) =520a(6) =672a(7) =888a(8) =1080a(9) =1120a(10) =1464a(11) =1480a(12) =1752a(13) =2440a(14) =2520a(15) =2808a(16) =2912a(17) =2920a(18) =3420a(19) =3768a(20) =3848a(21) =4632a(22) =5880a(23) =6048a(24) =6280a(25) =6344a(26) =6552a(27) =6648a(28) =6664a(29) =7512
External references
- oeis: A351447