Numbers k such that 3*k + 4 is prime

Open in the 3-D viewerA034936 on the OEIS
| Terms | 100,000 (n = 1 … 100,000) |
|---|---|
| Decomposable (a > 2d) | 99,997 |
| Level class, k > L | 26,624 · 26.62 % |
| Weight class, k ≤ L | 73,373 · 73.38 % |
| Ties, k = L | 39 |
| On the level line L = 1 | 16,340 |
| Forced level, l ≤ d² | 4 |
| Range of a(n) | 1 … 917,261 |
| Range of the jump d | 2 … 90 |
| Largest weight k, level L | 917,209, 305,729 |
39 different gaps occur, from 2 to 90; the level share is 26.62 %; L = 1 holds 61 % 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.