Primes p such that p + 8 is also prime

Open in the 3-D viewerA023202 on the OEIS
| Terms | 100,000 (n = 1 … 100,000) |
|---|---|
| Decomposable (a > 2d) | 99,996 |
| Level class, k > L | 46,999 · 47.00 % |
| Weight class, k ≤ L | 52,997 · 53.00 % |
| Ties, k = L | 0 |
| On the level line L = 1 | 17,163 |
| Forced level, l ≤ d² | 179 |
| Range of a(n) | 3 … 18,468,251 |
| Range of the jump d | 2 … 2,004 |
| Largest weight k, level L | 18,465,773, 1,672,387 |
Primes p with p + 8 prime. Past 3 every term is 5 mod 6 (p + 8 must avoid 3), so l = 5 (mod 6): no ties, by proof. The level share is 47.00 %; L = 1 holds 37 % 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.