A216572 - cp's OEIS frontend

A216572 Numbers n such that the n-th Lucas number is prime, but cannot be written in the form a^2 + 6*b^2.

n	a(n)
1	0
2	2
3	5
4	7
5	8
6	13
7	16
8	17
9	19
10	31
11	37
12	41
13	47
14	53
15	61
16	71
17	79
18	113
19	353
20	503
21	613
22	617
23	863
24	1097
25	1361
26	4793
27	5851
28	7741
29	8467
30	13963
31	19469
32	81671
33	89849
34	94823
35	140057
36	159521
37	183089
38	344293
39	443609
40	532277
41	574219
42	631181
43	637751
44	651821

[0, 2, 5, 7, 8, 13, 16, 17, 19, 31, 37, 41, 47, 53, 61, 71, 79, 113, 353, 503, 613, 617, 863, 1097, 1361, 4793, 5851, 7741, 8467, 13963, 19469, 81671, 89849, 94823, 140057, 159521, 183089, 344293, 443609, 532277, 574219, 631181, 637751, 651821]

cp's OEIS Frontend

A216572 Numbers n such that the n-th Lucas number is prime, but cannot be written in the form a^2 + 6*b^2.

Table of values

List of values