Primes p with prime(p) - p - 1 and prime(p) - p + 1 both prime

Open in the 3-D viewerA236119 on the OEIS
| Terms | 100,000 (n = 1 … 100,000) |
|---|---|
| Decomposable (a > 2d) | 99,994 |
| Level class, k > L | 56,982 · 56.99 % |
| Weight class, k ≤ L | 43,012 · 43.01 % |
| Ties, k = L | 1 |
| On the level line L = 1 | 7,491 |
| Forced level, l ≤ d² | 3,523 |
| Range of a(n) | 5 … 185,763,089 |
| Range of the jump d | 2 … 22,370 |
| Largest weight k, level L | 185,748,821, 61,737,829 |
4,892 different gaps occur, from 2 to 22,370; the level share is 56.99 %; 3.5 % of terms are forced level (l <= d^2); 6 terms do not decompose.
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.