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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 9409 |
| 3 | 332929 |
| 4 | 3690241 |
| 5 | 23049601 |
| 6 | 101626561 |
| 7 | 354079489 |
| 8 | 1040514049 |
| 9 | 2687489281 |
| 10 | 6272798401 |
| 11 | 13493377921 |
| 12 | 27138279169 |
| 13 | 51591216769 |
| 14 | 93489789121 |
| 15 | 162571046401 |
| 16 | 272735662081 |
| 17 | 443365544449 |
| 18 | 700932305089 |
| 19 | 1080936581761 |
| 20 | 1630220793601 |
| 21 | 2409700487041 |
[1,1,9409,332929,3690241,23049601,101626561, 354079489,1040514049,2687489281,6272798401, 13493377921,27138279169,51591216769,93489789121, 162571046401,272735662081,443365544449, 700932305089,1080936581761,1630220793601, 2409700487041] |