A018101 - OEIS

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A018101 as a simple table

n	a(n)
0	1
1	3
2	5
3	10
4	19
5	40
6	83
7	173
8	361
9	754
10	1574
11	3286
12	6859
13	14321
14	29898
15	62421
16	130321
17	272084
18	568057
19	1185987
20	2476099
21	5169594
22	10793066
23	22533737
24	47045881
25	98222279
26	205068241
27	428140988
28	893871739

[1,3,5,10,19,40,83,173,361,754,1574,3286,6859, 14321,29898,62421,130321,272084,568057,1185987, 2476099,5169594,10793066,22533737,47045881, 98222279,205068241,428140988,893871739]