login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A281490 as a simple table

na(n)
01
12
21
31
41
50
61
71
81
91
101
113
121
130
142
151
161
171
181
190
200
212
221
231
240
251
262
270
282
292
301
312
321
331
340
351
363
371
380
391
402
410
420
430
441
452
462
471
480
490
500
512
521
532
541
551
562
571
582
591
600
613
620
631
641
650
664
671
681
690
701
710
721
731
741
751
760
771
781
793
801
810
820
830
840
851
863

[1,2,1,1,1,0,1,1,1,1,1,3,1,0,2,1,1,1,1,0,0,2,1,1,
 0,1,2,0,2,2,1,2,1,1,0,1,3,1,0,1,2,0,0,0,1,2,2,1,0,
 0,0,2,1,2,1,1,2,1,2,1,0,3,0,1,1,0,4,1,1,0,1,0,1,1,
 1,1,0,1,1,3,1,0,0,0,0,1,3]