decompwlj 3D

Primes of the form x^2+74*y^2

A033248 on the OEIS · family quadratic form

Weight–level plate of Primes of the form x^2+74*y^2
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 viewerA033248 on the OEIS
Terms100,000 (n = 1 … 100,000)
Decomposable (a > 2d)99,999
Level class, k > L45,264 · 45.26 %
Weight class, k ≤ L54,735 · 54.74 %
Ties, k = L4
On the level line L = 18,064
Forced level, l ≤ d²520
Range of a(n)83 … 32,551,489
Range of the jump d2 … 3,822
Largest weight k, level L32,544,329, 10,829,989

850 different gaps occur, from 2 to 3,822; the level share is 45.26 %.

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.