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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 15 |
| 3 | 34 |
| 4 | 97 |
| 5 | 300 |
| 6 | 1036 |
| 7 | 3313 |
| 8 | 11075 |
| 9 | 37067 |
| 10 | 122922 |
| 11 | 407858 |
| 12 | 1357514 |
| 13 | 4523493 |
| 14 | 15101162 |
| 15 | 50477243 |
| 16 | 168866252 |
| 17 | 565232270 |
| 18 | 1892399523 |
| 19 | 6336697206 |
| 20 | 21221333391 |
| 21 | 71076453037 |
| 22 | 238076082776 |
| 23 | 797517130607 |
| 24 | 2671722364414 |
| 25 | 8950813865109 |
[2,15,34,97,300,1036,3313,11075,37067,122922, 407858,1357514,4523493,15101162,50477243, 168866252,565232270,1892399523,6336697206, 21221333391,71076453037,238076082776,797517130607, 2671722364414,8950813865109] |