A019091 - OEIS

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A019091 as a simple table

n	a(n)
3	0
4	1
5	0
6	10
7	0
8	15
9	9
10	93
11	62
12	404
13	410
14	2010
15	2518
16	10448
17	14529
18	53021
19	85015
20	284207
21	503286
22	1569257
23	3034547
24	8971190
25	18463901
26	52340847
27	113029843
28	310596655
29	696018082
30	1868954063
31	4310295664

[0,1,0,10,0,15,9,93,62,404,410,2010,2518,10448, 14529,53021,85015,284207,503286,1569257,3034547, 8971190,18463901,52340847,113029843,310596655, 696018082,1868954063,4310295664]