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Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 4 |
| 6 | 10 |
| 7 | 20 |
| 8 | 41 |
| 9 | 77 |
| 10 | 140 |
| 11 | 252 |
| 12 | 505 |
| 13 | 1000 |
| 14 | 1780 |
| 15 | 3652 |
| 16 | 7305 |
| 17 | 12545 |
| 18 | 25805 |
| 19 | 52325 |
| 20 | 88634 |
| 21 | 184736 |
| 22 | 379676 |
| 23 | 636524 |
| 24 | 1334942 |
| 25 | 2764139 |
| 26 | 4594244 |
| 27 | 9685364 |
| 28 | 20191604 |
| 29 | 33355944 |
| 30 | 70639794 |
| 31 | 148064400 |
| 32 | 243374923 |
| 33 | 517215283 |
[0,0,0,0,4,10,20,41,77,140,252,505,1000,1780,3652, 7305,12545,25805,52325,88634,184736,379676,636524, 1334942,2764139,4594244,9685364,20191604,33355944, 70639794,148064400,243374923,517215283] |