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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 29 |
| 4 | 127 |
| 5 | 526 |
| 6 | 2420 |
| 7 | 10624 |
| 8 | 49846 |
| 9 | 226007 |
| 10 | 1074831 |
| 11 | 4975408 |
| 12 | 23852322 |
| 13 | 111962249 |
| 14 | 540110364 |
| 15 | 2561114007 |
| 16 | 12409220893 |
| 17 | 59286982781 |
| 18 | 288292731330 |
| 19 | 1385471572325 |
| 20 | 6755689212401 |
| 21 | 32616834914307 |
| 22 | 159413239163978 |
| 23 | 772560860522906 |
| 24 | 3782992084218568 |
| 25 | 18390147847296445 |
| 26 | 90197700595782482 |
[1,2,8,29,127,526,2420,10624,49846,226007,1074831, 4975408,23852322,111962249,540110364,2561114007, 12409220893,59286982781,288292731330, 1385471572325,6755689212401,32616834914307, 159413239163978,772560860522906,3782992084218568, 18390147847296445,90197700595782482] |