A020756 - cp's OEIS frontend

A020756 Numbers that are the sum of two triangular numbers.

n	a(n)
1	0
2	1
3	2
4	3
5	4
6	6
7	7
8	9
9	10
10	11
11	12
12	13
13	15
14	16
15	18
16	20
17	21
18	22
19	24
20	25
21	27
22	28
23	29
24	30
25	31
26	34
27	36
28	37
29	38
30	39
31	42
32	43
33	45
34	46
35	48
36	49
37	51
38	55
39	56
40	57
41	58
42	60
43	61
44	64
45	65
46	66
47	67
48	69
49	70
50	72
51	73
52	76
53	78
54	79
55	81
56	83
57	84
58	87
59	88
60	90
61	91
62	92
63	93
64	94
65	97
66	99
67	100
68	101
69	102
70	105
71	106
72	108

[0, 1, 2, 3, 4, 6, 7, 9, 10, 11, 12, 13, 15, 16, 18, 20, 21, 22, 24, 25, 27, 28, 29, 30, 31, 34, 36, 37, 38, 39, 42, 43, 45, 46, 48, 49, 51, 55, 56, 57, 58, 60, 61, 64, 65, 66, 67, 69, 70, 72, 73, 76, 78, 79, 81, 83, 84, 87, 88, 90, 91, 92, 93, 94, 97, 99, 100, 101, 102, 105, 106, 108]

cp's OEIS Frontend

A020756 Numbers that are the sum of two triangular numbers.

Table of values

List of values

n	a(n)
1	0
2	1
3	2
4	3
5	4
6	6
7	7
8	9
9	10
10	11
11	12
12	13
13	15
14	16
15	18
16	20
17	21
18	22
19	24
20	25
21	27
22	28
23	29
24	30
25	31
26	34
27	36
28	37
29	38
30	39
31	42
32	43
33	45
34	46
35	48
36	49
37	51
38	55
39	56
40	57
41	58
42	60
43	61
44	64
45	65
46	66
47	67
48	69
49	70
50	72
51	73
52	76
53	78
54	79
55	81
56	83
57	84
58	87
59	88
60	90
61	91
62	92
63	93
64	94
65	97
66	99
67	100
68	101
69	102
70	105
71	106
72	108

n	a(n)
1	0
2	1
3	2
4	3
5	4
6	6
7	7
8	9
9	10
10	11
11	12
12	13
13	15
14	16
15	18
16	20
17	21
18	22
19	24
20	25
21	27
22	28
23	29
24	30
25	31
26	34
27	36
28	37
29	38
30	39
31	42
32	43
33	45
34	46
35	48
36	49
37	51
38	55
39	56
40	57
41	58
42	60
43	61
44	64
45	65
46	66
47	67
48	69
49	70
50	72
51	73
52	76
53	78
54	79
55	81
56	83
57	84
58	87
59	88
60	90
61	91
62	92
63	93
64	94
65	97
66	99
67	100
68	101
69	102
70	105
71	106
72	108

n	a(n)
1	0
2	1
3	2
4	3
5	4
6	6
7	7
8	9
9	10
10	11
11	12
12	13
13	15
14	16
15	18
16	20
17	21
18	22
19	24
20	25
21	27
22	28
23	29
24	30
25	31
26	34
27	36
28	37
29	38
30	39
31	42
32	43
33	45
34	46
35	48
36	49
37	51
38	55
39	56
40	57
41	58
42	60
43	61
44	64
45	65
46	66
47	67
48	69
49	70
50	72
51	73
52	76
53	78
54	79
55	81
56	83
57	84
58	87
59	88
60	90
61	91
62	92
63	93
64	94
65	97
66	99
67	100
68	101
69	102
70	105
71	106
72	108