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A004180 as a simple table

na(n)
00
11
22
33
44
50
66
77
88
99
1010
1111
1212
1313
1414
151
1616
1717
1818
1919
2020
2121
2222
2323
2424
252
2626
2727
2828
2929
3030
3131
3232
3333
3434
353
3636
3737
3838
3939
4040
4141
4242
4343
4444
454
4646
4747
4848
4949
500
511
522
533
544
550
566
577
588
599
6060
6161
6262
6363
6464
656
6666
6767
6868
6969
7070
7171
7272
7373
7474

[0,1,2,3,4,0,6,7,8,9,10,11,12,13,14,1,16,17,18,19,
 20,21,22,23,24,2,26,27,28,29,30,31,32,33,34,3,36,
 37,38,39,40,41,42,43,44,4,46,47,48,49,0,1,2,3,4,0,
 6,7,8,9,60,61,62,63,64,6,66,67,68,69,70,71,72,73,
 74]