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A281717 as a simple table

n a(n)
1 4
2 4
3 8
4 38
5 90
6 305
7 902
8 2710
9 8376
10 25226
11 77145
12 235122
13 715882
14 2186483
15 6666846
16 20353268
17 62140942
18 189739429
19 579567532
20 1770391431
21 5409031357
22 16528102350
23 50508922108
24 154369025240
25 471828803722
26 1442250315610
27 4408832591287

[4,4,8,38,90,305,902,2710,8376,25226,77145,235122,
 715882,2186483,6666846,20353268,62140942,
 189739429,579567532,1770391431,5409031357,
 16528102350,50508922108,154369025240,471828803722,
 1442250315610,4408832591287]

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Last modified December 9 01:52 EST 2021. Contains 349625 sequences. (Running on oeis4.)