Numbers n with the property that, if tau(n) = k = number of divisors of n, and the d(i) are the divisors [arranged in increasing order], then the sum 1/d(k) + 1/d(k-1) + 1/d(k-2) + ... + 1/d(q) is an integer for some q.
A226476
Numbers n with the property that, if tau(n) = k = number of divisors of n, and the d(i) are the divisors [arranged in increasing order], then the sum 1/d(k) + 1/d(k-1) + 1/d(k-2) + ... + 1/d(q) is an integer for some q.
Terms
- a(0) =1a(1) =6a(2) =24a(3) =28a(4) =120a(5) =496a(6) =672a(7) =2016a(8) =4320a(9) =4680a(10) =8128a(11) =8190a(12) =26208a(13) =30240a(14) =32760a(15) =42336a(16) =45864a(17) =392448a(18) =523776a(19) =714240a(20) =1571328a(21) =2178540a(22) =8910720a(23) =17428320a(24) =20427264a(25) =23569920a(26) =29795040a(27) =33550336a(28) =34369920a(29) =45532800
External references
- oeis: A226476