A041890 - OEIS

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A041890 as a simple table

n	a(n)
0	21
1	22
2	43
3	65
4	108
5	389
6	1275
7	27164
8	82767
9	275465
10	358232
11	633697
12	991929
13	1625626
14	69268221
15	70893847
16	140162068
17	211055915
18	351217983
19	1264709864
20	4145347575
21	88317008939
22	269096374392
23	895606132115

[21,22,43,65,108,389,1275,27164,82767,275465, 358232,633697,991929,1625626,69268221,70893847, 140162068,211055915,351217983,1264709864, 4145347575,88317008939,269096374392,895606132115]