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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 2 |
| 7 | 3 |
| 8 | 3 |
| 9 | 4 |
| 10 | 5 |
| 11 | 6 |
| 12 | 7 |
| 13 | 9 |
| 14 | 10 |
| 15 | 12 |
| 16 | 14 |
| 17 | 17 |
| 18 | 19 |
| 19 | 23 |
| 20 | 26 |
| 21 | 30 |
| 22 | 35 |
| 23 | 40 |
| 24 | 46 |
| 25 | 52 |
| 26 | 60 |
| 27 | 67 |
| 28 | 77 |
| 29 | 87 |
| 30 | 98 |
| 31 | 111 |
| 32 | 124 |
| 33 | 140 |
| 34 | 157 |
| 35 | 175 |
| 36 | 197 |
| 37 | 219 |
| 38 | 244 |
| 39 | 272 |
| 40 | 302 |
| 41 | 336 |
| 42 | 372 |
| 43 | 412 |
| 44 | 456 |
| 45 | 503 |
| 46 | 556 |
| 47 | 613 |
| 48 | 675 |
| 49 | 742 |
| 50 | 816 |
| 51 | 896 |
| 52 | 983 |
| 53 | 1078 |
| 54 | 1180 |
| 55 | 1291 |
| 56 | 1411 |
| 57 | 1542 |
| 58 | 1683 |
| 59 | 1836 |
| 60 | 2001 |
| 61 | 2178 |
[0,1,1,1,2,2,3,3,4,5,6,7,9,10,12,14,17,19,23,26, 30,35,40,46,52,60,67,77,87,98,111,124,140,157,175, 197,219,244,272,302,336,372,412,456,503,556,613, 675,742,816,896,983,1078,1180,1291,1411,1542,1683, 1836,2001,2178] |