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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 7 |
| 4 | 19 |
| 5 | 35 |
| 6 | 95 |
| 7 | 225 |
| 8 | 575 |
| 9 | 1563 |
| 10 | 4179 |
| 11 | 11555 |
| 12 | 32259 |
| 13 | 90327 |
| 14 | 255307 |
| 15 | 723255 |
| 16 | 2054259 |
| 17 | 5847519 |
| 18 | 16660707 |
| 19 | 47512875 |
| 20 | 135574255 |
| 21 | 386984391 |
| 22 | 1104913059 |
| 23 | 3155268051 |
| 24 | 9011441543 |
| 25 | 25738758919 |
| 26 | 73519704603 |
| 27 | 210007895555 |
| 28 | 599899095903 |
[1,7,7,19,35,95,225,575,1563,4179,11555,32259, 90327,255307,723255,2054259,5847519,16660707, 47512875,135574255,386984391,1104913059, 3155268051,9011441543,25738758919,73519704603, 210007895555,599899095903] |