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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 14 |
| 6 | 64 |
| 7 | 218 |
| 8 | 692 |
| 9 | 1982 |
| 10 | 5496 |
| 11 | 14562 |
| 12 | 37692 |
| 13 | 95142 |
| 14 | 236032 |
| 15 | 576074 |
| 16 | 1387780 |
| 17 | 3304078 |
| 18 | 7787656 |
| 19 | 18190386 |
| 20 | 42151116 |
| 21 | 96972534 |
| 22 | 221651472 |
| 23 | 503650970 |
| 24 | 1138286740 |
| 25 | 2559944414 |
| 26 | 5731095704 |
| 27 | 12776843138 |
| 28 | 28374100572 |
[0,0,0,0,0,14,64,218,692,1982,5496,14562,37692, 95142,236032,576074,1387780,3304078,7787656, 18190386,42151116,96972534,221651472,503650970, 1138286740,2559944414,5731095704,12776843138, 28374100572] |