Numbers n such that n + 3 and n - 3 are both prime

Open in the 3-D viewerA087695 on the OEIS
| Terms | 100,000 (n = 1 … 100,000) |
|---|---|
| Decomposable (a > 2d) | 100,000 |
| Level class, k > L | 30,017 · 30.02 % |
| Weight class, k ≤ L | 69,983 · 69.98 % |
| Ties, k = L | 2 |
| On the level line L = 1 | 1 |
| Forced level, l ≤ d² | 76 |
| Range of a(n) | 8 … 8,319,530 |
| Range of the jump d | 2 … 1,044 |
| Largest weight k, level L | 4,159,523, 2,772,804 |
351 different gaps occur, from 2 to 1,044; the level share is 30.02 %.
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.