cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A380909 a(n) = numerator(n!! / (n - 1)!!).

Table of values

n a(n)
0 1
1 1
2 2
3 3
4 8
5 15
6 16
7 35
8 128
9 315
10 256
11 693
12 1024
13 3003
14 2048
15 6435
16 32768
17 109395
18 65536
19 230945
20 262144
21 969969
22 524288
23 2028117
24 4194304
25 16900975
26 8388608
27 35102025
28 33554432
29 145422675
30 67108864
31 300540195
32 2147483648
33 9917826435
34 4294967296
35 20419054425

List of values

[1, 1, 2, 3, 8, 15, 16, 35, 128, 315, 256, 693, 1024, 3003, 2048, 6435, 32768, 109395, 65536, 230945, 262144, 969969, 524288, 2028117, 4194304, 16900975, 8388608, 35102025, 33554432, 145422675, 67108864, 300540195, 2147483648, 9917826435, 4294967296, 20419054425]