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A023847 as a simple table

na(n)
00
12
24
34
46
58
68
711
811
911
1013
1113
1213
1318
1416
1517
1617
1719
1818
1918
2022
2124
2221
2323
2423
2524
2628
2726
2826
2930
3029
3132
3228
3330
3431
3531
3632
3735
3835
3936
4036
4136
4237
4333
4435
4538
4636
4739
4836
4940
5040
5141
5245
5348
5443
5546
5646
5745
5850
5947
6049
6152
6252
6349
6446
6551
6651
6750
6850
6955
7051
7157
7254
7357
7457
7555
7659
7762

[0,2,4,4,6,8,8,11,11,11,13,13,13,18,16,17,17,19,
 18,18,22,24,21,23,23,24,28,26,26,30,29,32,28,30,
 31,31,32,35,35,36,36,36,37,33,35,38,36,39,36,40,
 40,41,45,48,43,46,46,45,50,47,49,52,52,49,46,51,
 51,50,50,55,51,57,54,57,57,55,59,62]