decompwlj 3D

Evenish numbers (prime to 10 and 10's digit is even)

A045797 on the OEIS · family residue class

Weight–level plate of Evenish numbers (prime to 10 and 10's digit is even)
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 viewerA045797 on the OEIS
Terms100,000 (n = 1 … 100,000)
Decomposable (a > 2d)99,997
Level class, k > L21,584 · 21.58 %
Weight class, k ≤ L78,413 · 78.42 %
Ties, k = L1
On the level line L = 115,589
Forced level, l ≤ d²7
Range of a(n)1 … 499,989
Range of the jump d2 … 12
Largest weight k, level L499,979, 166,655

The gaps are 2, 4 and 12; the level share is 21.58 %; L = 1 holds 72 % 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.