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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.

A121943 Numbers k such that the central binomial coefficient C(2k,k) is divisible by k^2.

Table of values

n a(n)
1 1
2 924
3 1287
4 2002
5 2145
6 3366
7 3640
8 3740
9 4199
10 6006
11 6118
12 6552
13 7480
14 7920
15 8580
16 8855
17 10465
18 10920
19 11385
20 11592
21 12285
22 12325
23 12441
24 12540
25 12597
26 12920
27 13224
28 13398
29 13566
30 15080
31 15834
32 18270
33 18354
34 18837
35 18972
36 19227
37 23562
38 23870
39 25641
40 25740

List of values

[1, 924, 1287, 2002, 2145, 3366, 3640, 3740, 4199, 6006, 6118, 6552, 7480, 7920, 8580, 8855, 10465, 10920, 11385, 11592, 12285, 12325, 12441, 12540, 12597, 12920, 13224, 13398, 13566, 15080, 15834, 18270, 18354, 18837, 18972, 19227, 23562, 23870, 25641, 25740]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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