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A028641 as a simple table

na(n)
01
12
20
30
42
54
60
74
80
92
100
114
120
130
140
150
162
174
180
192
204
210
220
234
240
256
260
270
284
290
300
310
320
330
340
358
362
370
380
390
400
410
420
434
444
454
460
474
480
496
500
510
520
530
540
558
560
570
580
590
600
614
620
634
642
650
660
670
684
690
700
710
720
734
740
750
762
778
780
790
804
812
820
834
840
858
860
870
880
890
900
910
924
930
940
954
960
970
980
994
1006
1014
1020
1030
1040

[1,2,0,0,2,4,0,4,0,2,0,4,0,0,0,0,2,4,0,2,4,0,0,4,
 0,6,0,0,4,0,0,0,0,0,0,8,2,0,0,0,0,0,0,4,4,4,0,4,0,
 6,0,0,0,0,0,8,0,0,0,0,0,4,0,4,2,0,0,0,4,0,0,0,0,4,
 0,0,2,8,0,0,4,2,0,4,0,8,0,0,0,0,0,0,4,0,0,4,0,0,0,
 4,6,4,0,0,0]