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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 6 |
| 6 | 9 |
| 7 | 17 |
| 8 | 23 |
| 9 | 40 |
| 10 | 87 |
| 11 | 111 |
| 12 | 219 |
| 13 | 336 |
| 14 | 413 |
| 15 | 614 |
| 16 | 1083 |
| 17 | 1850 |
| 18 | 2198 |
| 19 | 3630 |
| 20 | 5007 |
| 21 | 5861 |
| 22 | 9282 |
| 23 | 12488 |
| 24 | 19232 |
| 25 | 33439 |
| 26 | 43709 |
| 27 | 49871 |
| 28 | 64671 |
| 29 | 73506 |
| 30 | 94625 |
| 31 | 221265 |
| 32 | 279516 |
| 33 | 394170 |
| 34 | 441250 |
| 35 | 766262 |
| 36 | 853692 |
| 37 | 1175344 |
| 38 | 1608014 |
| 39 | 1975108 |
| 40 | 2675925 |
[1,1,2,3,6,9,17,23,40,87,111,219,336,413,614,1083, 1850,2198,3630,5007,5861,9282,12488,19232,33439, 43709,49871,64671,73506,94625,221265,279516, 394170,441250,766262,853692,1175344,1608014, 1975108,2675925] |