2146992128
domain: N
Appears in sequences
- Numbers whose abundance is 14.at n=5A141546
- Numbers k such that sigma(k) == 0 (mod k+7).at n=6A274559
- Practical numbers (A005153) that are abundant and have a record low value of abundancy index.at n=28A362052
- Primitive abundant numbers k (A071395) whose abundancy index sigma(k)/k has a record low value.at n=31A362053
- a(n) = 2^(2*n - 1) - 2^(n - 1)*(n - 1).at n=16A376585