Same numbers of prime factors of forms 4*k+1 and 4*k+3, counted with multiplicity

Open in the 3-D viewerA072202 on the OEIS
| Terms | 100,000 (n = 1 … 100,000) |
|---|---|
| Decomposable (a > 2d) | 99,995 |
| Level class, k > L | 15,988 · 15.99 % |
| Weight class, k ≤ L | 84,007 · 84.01 % |
| Ties, k = L | 24 |
| On the level line L = 1 | 7,900 |
| Forced level, l ≤ d² | 6 |
| Range of a(n) | 1 … 461,422 |
| Range of the jump d | 1 … 43 |
| Largest weight k, level L | 461,381, 230,698 |
40 different gaps occur, from 1 to 43; the level share is 15.99 %; L = 1 holds 49 % 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.