A342326 - cp's OEIS frontend

A342326 a(n) is the smallest nonnegative integer that can be written as a sum of two distinct nonzero triangular numbers in exactly n ways or -1 if no such integer exists.

n	a(n)
0	0
1	4
2	16
3	81
4	471
5	2031
6	1381
7	11781
8	6906
9	17956
10	34531
11	123256
12	40056
13	305256
14	863281
15	448906
16	200281
17	1957231
18	520731
19	10563906
20	1001406
21	11222656
22	7631406
23	3454506
24	1482081
25	75865156
26	7172606106
27	8852431
28	25035156
29	334020781
30	13018281
31	38531031
32	7410406
33	7014160156

[0, 4, 16, 81, 471, 2031, 1381, 11781, 6906, 17956, 34531, 123256, 40056, 305256, 863281, 448906, 200281, 1957231, 520731, 10563906, 1001406, 11222656, 7631406, 3454506, 1482081, 75865156, 7172606106, 8852431, 25035156, 334020781, 13018281, 38531031, 7410406, 7014160156]

cp's OEIS Frontend

A342326 a(n) is the smallest nonnegative integer that can be written as a sum of two distinct nonzero triangular numbers in exactly n ways or -1 if no such integer exists.

Table of values

List of values