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A173072 as a simple table

na(n)
12
21
31
41
53
63
75
85
97
1011
1111
1215
1317
1417
1519
1623
1727
1827
1931
2033
2133
2237
2339
2443
2549
2651
2751
2853
2953
3055
3167
3269
3373
3473
3581
3681
3785
3889
3991
4095
4199
4299
43107
44107
45109
46109
47119
48129
49131
50131
51133
52137
53137
54145
55149
56153
57157
58157
59161
60163
61163
62171
63183
64185

[2,1,1,1,3,3,5,5,7,11,11,15,17,17,19,23,27,27,31,
 33,33,37,39,43,49,51,51,53,53,55,67,69,73,73,81,
 81,85,89,91,95,99,99,107,107,109,109,119,129,131,
 131,133,137,137,145,149,153,157,157,161,163,163,
 171,183,185]