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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 3 |
| 7 | 15 |
| 8 | 28 |
| 9 | 69 |
| 10 | 111 |
| 11 | 259 |
| 12 | 336 |
| 13 | 671 |
| 14 | 906 |
| 15 | 1355 |
| 16 | 1769 |
| 17 | 2961 |
| 18 | 3461 |
| 19 | 5438 |
| 20 | 6501 |
| 21 | 8613 |
| 22 | 10371 |
| 23 | 15022 |
| 24 | 16807 |
| 25 | 22759 |
| 26 | 26512 |
| 27 | 33090 |
| 28 | 37822 |
| 29 | 50603 |
| 30 | 54583 |
| 31 | 71528 |
| 32 | 80768 |
| 33 | 96067 |
| 34 | 107756 |
| 35 | 131271 |
| 36 | 141215 |
| 37 | 177195 |
| 38 | 196173 |
| 39 | 227094 |
| 40 | 246828 |
[0,0,0,0,1,3,15,28,69,111,259,336,671,906,1355, 1769,2961,3461,5438,6501,8613,10371,15022,16807, 22759,26512,33090,37822,50603,54583,71528,80768, 96067,107756,131271,141215,177195,196173,227094, 246828] |