Primes p such that p + 4 is prime and p == 9 (mod 10)

Open in the 3-D viewerA074822 on the OEIS
| Terms | 100,000 (n = 1 … 100,000) |
|---|---|
| Decomposable (a > 2d) | 99,997 |
| Level class, k > L | 57,941 · 57.94 % |
| Weight class, k ≤ L | 42,056 · 42.06 % |
| Ties, k = L | 30 |
| On the level line L = 1 | 20,626 |
| Forced level, l ≤ d² | 956 |
| Range of a(n) | 19 … 64,904,629 |
| Range of the jump d | 30 … 7,020 |
| Largest weight k, level L | 64,897,759, 2,058,199 |
193 different gaps occur, from 30 to 7,020; the level share is 57.94 %; L = 1 holds 36 % 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.