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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 248 |
| 2 | 4119 |
| 3 | 33512 |
| 4 | 192513 |
| 5 | 885480 |
| 6 | 3493982 |
| 7 | 12288992 |
| 8 | 39493539 |
| 9 | 117966288 |
| 10 | 331534572 |
| 11 | 884736744 |
| 12 | 2257837845 |
| 13 | 5541103056 |
| 14 | 13136687601 |
| 15 | 30197680312 |
| 16 | 67515206970 |
| 17 | 147197952744 |
| 18 | 313645814923 |
| 19 | 654403831496 |
| 20 | 1339190286960 |
| 21 | 2691907586232 |
| 22 | 5321761716339 |
| 23 | 10359073015248 |
[1,248,4119,33512,192513,885480,3493982,12288992, 39493539,117966288,331534572,884736744,2257837845, 5541103056,13136687601,30197680312,67515206970, 147197952744,313645814923,654403831496, 1339190286960,2691907586232,5321761716339, 10359073015248] |