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n  a(n)  factorization
3  2     prime
4  3     prime
5  23    prime
6  4     2^2
7  235   5 * 47
8  35    5 * 7
9  26    2 * 13
10 347   prime
11 237   3 * 79
12 58    2 * 29
13 2359  7 * 337
14 349   prime
15 2610  2 * 3^2 * 5 * 29
16 311   prime
17 235711  7 * 151 * 223
18 45712 2^4 * 2857
19 2313  3^2 * 257
20 3813  3 * 31 * 41
21 2614 2 * 1307
22 345915 3^2 * 5 * 7687
23 235915 5 * 29 * 1627
24 716   2^2 * 179
25 2371017 3 * 11 * 71849
26 3417 3 * 17 * 67
27 2561118 2 * 3 * 7 * 17^2 * 211
28 3581119 37 * 96787
29 2319  3 * 773
30 41220 2^2 * 3^2 * 5 * 229
31 237921 3 * 71 * 1117
32 35791321 37 * 967333
33 2561322 2 * 3 * 17 * 25111
34 3423  3 * 7 * 163
35 23101423 97 * 238159
36 824    2^3 * 103
37 2351525 5^2 * 11 * 17 * 503
38 3457111525 5^2 * 7 * 97 * 203659
39 2671126 2 * 1335563
40 391627 prime
41 23927   71 * 337
42 45121728 2^6 * 3 * 235009
43 2351729  17 * 138337
44 3829  7 * 547
45 26710131830 2 * 5 * 41^2 * 757 * 2099
46 3471331 prime
47 2351931 3 * 523 * 1499
48 51932 2^2 * 12983
49 239111433 3^4 * 11 * 43 * 79^2
50 349112033 12119 * 28807
51 2634  2 * 3 * 439
52 3578152135 5 * 79 * 9058613
53 2357152135 5 * 13 * 36263879
54 41236 2^2 * 13^2 * 61
55 23102237 73 * 316469
56 31637 17 * 1861
57 2562338 2 * 23 * 53 * 1051
58 3459132339 3 * 13 * 1229 * 72169
59 2379131739 3^2 * 877 * 301423
60 7811172440 2^3 * 5 * 195279311
61 231141 3 * 77047
62 3452541 3 * 1150847
...