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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 21 |
| 5 | 70 |
| 6 | 205 |
| 7 | 536 |
| 8 | 1264 |
| 9 | 2722 |
| 10 | 5424 |
| 11 | 10122 |
| 12 | 17871 |
| 13 | 30102 |
| 14 | 48703 |
| 15 | 76108 |
| 16 | 115394 |
| 17 | 170386 |
| 18 | 245770 |
| 19 | 347214 |
| 20 | 481497 |
| 21 | 656646 |
| 22 | 882081 |
| 23 | 1168768 |
| 24 | 1529380 |
| 25 | 1978466 |
| 26 | 2532628 |
| 27 | 3210706 |
| 28 | 4033971 |
| 29 | 5026326 |
| 30 | 6214515 |
| 31 | 7628340 |
| 32 | 9300886 |
| 33 | 11268754 |
| 34 | 13572302 |
| 35 | 16255894 |
| 36 | 19368157 |
| 37 | 22962246 |
[1,1,2,6,21,70,205,536,1264,2722,5424,10122,17871, 30102,48703,76108,115394,170386,245770,347214, 481497,656646,882081,1168768,1529380,1978466, 2532628,3210706,4033971,5026326,6214515,7628340, 9300886,11268754,13572302,16255894,19368157, 22962246] |