Ion
No. of lines
Lines with
transition
probabilities
Lines with
level
designations
N I
1309
1287
1287
N II
809
786
786
N III
1378
1359
1359
N IV
536
531
531
N V
442
402
433
N VI
91
90
91
N VII
137
137
137
Total:
4702
4592
4624