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A199853 as a simple table

na(n)
01
1-1
2-1
3-3
4-6
5-14
6-31
7-70
8-157
9-353
10-793
11-1782
12-4004
13-8997
14-20216
15-45425
16-102069
17-229347
18-515338
19-1157954
20-2601899
21-5846414
22-13136773
23-29518061
24-66326481
25-149034250
26-334876920
27-752461609
28-1690765888
29-3799116465
30-8536537209

[1,-1,-1,-3,-6,-14,-31,-70,-157,-353,-793,-1782,
 -4004,-8997,-20216,-45425,-102069,-229347,-515338,
 -1157954,-2601899,-5846414,-13136773,-29518061,
 -66326481,-149034250,-334876920,-752461609,
 -1690765888,-3799116465,-8536537209]