Numbers such that the sum of cubes of their prime factors (taken with multiplicity) is a prime

Open in the 3-D viewerA134618 on the OEIS
| Terms | 100,000 (n = 1 … 100,000) |
|---|---|
| Decomposable (a > 2d) | 99,999 |
| Level class, k > L | 28,281 · 28.28 % |
| Weight class, k ≤ L | 71,718 · 71.72 % |
| Ties, k = L | 11 |
| On the level line L = 1 | 7,199 |
| Forced level, l ≤ d² | 37 |
| Range of a(n) | 12 … 2,753,658 |
| Range of the jump d | 1 … 290 |
| Largest weight k, level L | 2,753,453, 1,375,273 |
229 different gaps occur, from 1 to 290; the level share is 28.28 %.
The decomposition
Every term of a strictly increasing sequence is written a(n) = k(n)·L(n) + d(n): the jump d = a(n+1) − a(n), the weight k the least divisor of a − d greater than d, the level L = (a − d)/k. A term decomposes when a > 2d; it is in the level class when k > L and in the weight class when k ≤ L. See decompwlj.com and arXiv:0711.0865, or how it works, with worked examples and a live one.