A056399 - OEIS

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A056399 as a simple table

n	a(n)
1	0
2	0
3	0
4	0
5	1
6	9
7	26
8	299
9	1183
10	10701
11	24736
12	349241
13	626053
14	6680979
15	26364610
16	137247254
17	353304459
18	4826418027
19	8199440662
20	93679529503
21	315943737331
22	1913783074461
23	4382586624256
24	60629067776483

[0,0,0,0,1,9,26,299,1183,10701,24736,349241, 626053,6680979,26364610,137247254,353304459, 4826418027,8199440662,93679529503,315943737331, 1913783074461,4382586624256,60629067776483]