Numbers n such that 5*n + 7 is prime

Open in the 3-D viewerA111224 on the OEIS
| Terms | 100,000 (n = 1 … 100,000) |
|---|---|
| Decomposable (a > 2d) | 99,996 |
| Level class, k > L | 20,221 · 20.22 % |
| Weight class, k ≤ L | 79,775 · 79.78 % |
| Ties, k = L | 3 |
| On the level line L = 1 | 1 |
| Forced level, l ≤ d² | 7 |
| Range of a(n) | 0 … 1,159,688 |
| Range of the jump d | 2 … 100 |
| Largest weight k, level L | 579,737, 289,912 |
48 different gaps occur, from 2 to 100; the level share is 20.22 %; L = 2 holds 46 % of the level class.
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.