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A009679 as a simple table

n a(n)
1 1
2 2
3 4
4 18
5 60
6 252
7 1860
8 9552
9 59616
10 565920
11 4051872
12 33805440
13 465239808
14 4294865664
15 35413136640
16 768372168960
17 8757710173440
18 79772814777600
19 1986906367584000
20 22082635812268800
21 280886415019776000
22 7683780010315046400

[1,2,4,18,60,252,1860,9552,59616,565920,4051872,
 33805440,465239808,4294865664,35413136640,
 768372168960,8757710173440,79772814777600,
 1986906367584000,22082635812268800,
 280886415019776000,7683780010315046400]

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Last modified December 13 23:14 EST 2019. Contains 329974 sequences. (Running on oeis4.)