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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.

A082595 Let QR be the set of quadratic residues mod n: QR = {x^2 mod n, 1 <= x <= n-1}. Let MR be the set of values taken by 2^x mod n: MR = {2^x mod n, 0 <= x <= n-2}. Usually if QR is a subset of MR then n is prime and otherwise n is composite. Sequence gives numbers that violate this rule, i.e., composites where QR is a subset of MR and primes where QR is not a subset of MR.

Table of values

n a(n)
1 4
2 8
3 31
4 43
5 73
6 89
7 109
8 113
9 127
10 151
11 157
12 223
13 229
14 233
15 241
16 251
17 257
18 277
19 281
20 283
21 307
22 331
23 337
24 353
25 397
26 431
27 433
28 439
29 457
30 499
31 571
32 577
33 593
34 601
35 617
36 631
37 641
38 643
39 673
40 683
41 691
42 727
43 733
44 739
45 811
46 881
47 911
48 919
49 937
50 953
51 971
52 997
53 1013

List of values

[4, 8, 31, 43, 73, 89, 109, 113, 127, 151, 157, 223, 229, 233, 241, 251, 257, 277, 281, 283, 307, 331, 337, 353, 397, 431, 433, 439, 457, 499, 571, 577, 593, 601, 617, 631, 641, 643, 673, 683, 691, 727, 733, 739, 811, 881, 911, 919, 937, 953, 971, 997, 1013]

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