decompwlj 3D

Numbers n such that 2*n^2 + 9 is prime

A111040 on the OEIS · family prime values

Weight–level plate of Numbers n such that 2*n^2 + 9 is prime
Click the plate to explore it in 3-D. Weight k across, level L up, both on log scales: blue in the weight class (k ≤ L), orange in the level class (k > L). The dashed diagonal is k = L.
Open in the 3-D viewerA111040 on the OEIS
Terms100,000 (n = 1 … 100,000)
Decomposable (a > 2d)99,998
Level class, k > L17,871 · 17.87 %
Weight class, k ≤ L82,127 · 82.13 %
Ties, k = L14
On the level line L = 15,126
Forced level, l ≤ d²4
Range of a(n)1 … 909,788
Range of the jump d1 … 84
Largest weight k, level L909,697, 454,785

77 different gaps occur, from 1 to 84; the level share is 17.87 %.

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.