A031407 - cp's OEIS frontend

A031407 Numbers k such that the continued fraction for sqrt(k) has even period 2*m and the m-th term of the periodic part is 4.

n	a(n)
1	18
2	22
3	34
4	39
5	57
6	68
7	69
8	76
9	78
10	92
11	105
12	108
13	116
14	124
15	140
16	150
17	155
18	174
19	186
20	203
21	205
22	217
23	220
24	259
25	264
26	266
27	282
28	294
29	301
30	308
31	318
32	329
33	333
34	369
35	371
36	376
37	378
38	406
39	410
40	413
41	423
42	434
43	450
44	456
45	477
46	490
47	495
48	504
49	517
50	522
51	549
52	550
53	558

[18, 22, 34, 39, 57, 68, 69, 76, 78, 92, 105, 108, 116, 124, 140, 150, 155, 174, 186, 203, 205, 217, 220, 259, 264, 266, 282, 294, 301, 308, 318, 329, 333, 369, 371, 376, 378, 406, 410, 413, 423, 434, 450, 456, 477, 490, 495, 504, 517, 522, 549, 550, 558]

cp's OEIS Frontend

A031407 Numbers k such that the continued fraction for sqrt(k) has even period 2*m and the m-th term of the periodic part is 4.

Table of values

List of values

n	a(n)
1	18
2	22
3	34
4	39
5	57
6	68
7	69
8	76
9	78
10	92
11	105
12	108
13	116
14	124
15	140
16	150
17	155
18	174
19	186
20	203
21	205
22	217
23	220
24	259
25	264
26	266
27	282
28	294
29	301
30	308
31	318
32	329
33	333
34	369
35	371
36	376
37	378
38	406
39	410
40	413
41	423
42	434
43	450
44	456
45	477
46	490
47	495
48	504
49	517
50	522
51	549
52	550
53	558

n	a(n)
1	18
2	22
3	34
4	39
5	57
6	68
7	69
8	76
9	78
10	92
11	105
12	108
13	116
14	124
15	140
16	150
17	155
18	174
19	186
20	203
21	205
22	217
23	220
24	259
25	264
26	266
27	282
28	294
29	301
30	308
31	318
32	329
33	333
34	369
35	371
36	376
37	378
38	406
39	410
40	413
41	423
42	434
43	450
44	456
45	477
46	490
47	495
48	504
49	517
50	522
51	549
52	550
53	558

n	a(n)
1	18
2	22
3	34
4	39
5	57
6	68
7	69
8	76
9	78
10	92
11	105
12	108
13	116
14	124
15	140
16	150
17	155
18	174
19	186
20	203
21	205
22	217
23	220
24	259
25	264
26	266
27	282
28	294
29	301
30	308
31	318
32	329
33	333
34	369
35	371
36	376
37	378
38	406
39	410
40	413
41	423
42	434
43	450
44	456
45	477
46	490
47	495
48	504
49	517
50	522
51	549
52	550
53	558