A216576 - cp's OEIS frontend

A216576 Numbers n such that n-th Lucas number is prime, but cannot be written in the form a^2 + 10*b^2.

n	a(n)
1	0
2	2
3	4
4	7
5	8
6	11
7	16
8	19
9	31
10	47
11	71
12	79
13	503
14	863
15	4787
16	5851
17	8467
18	10691
19	12251
20	13963
21	36779
22	44507
23	56003
24	81671
25	94823
26	148091
27	202667
28	574219
29	616787
30	637751
31	692147

[0, 2, 4, 7, 8, 11, 16, 19, 31, 47, 71, 79, 503, 863, 4787, 5851, 8467, 10691, 12251, 13963, 36779, 44507, 56003, 81671, 94823, 148091, 202667, 574219, 616787, 637751, 692147]

cp's OEIS Frontend

A216576 Numbers n such that n-th Lucas number is prime, but cannot be written in the form a^2 + 10*b^2.

Table of values

List of values