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A281267 as a simple table

na(n)
01
1-1
2-3
38
413
5-51
6-120
7538
8781
9-5419
10-3053
1147673
125080
13-427740
14136462
153922383
16-3278067
17-34819588
1848561567
19299316651
20-603368637
21-2509708844
226948730643
2320210062532
24-76150197416
25-152569240051
26801154765564
271039352472008
28-8158396721266

[1,-1,-3,8,13,-51,-120,538,781,-5419,-3053,47673,
 5080,-427740,136462,3922383,-3278067,-34819588,
 48561567,299316651,-603368637,-2509708844,
 6948730643,20210062532,-76150197416,-152569240051,
 801154765564,1039352472008,-8158396721266]