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”).

A220691 as a simple table

na(n)
10
20
31
40
50
63
70
81
91
106
110
120
131
142
1510
160
170
181
192
204
2115
220
230
241
251
264
276
2821
290
300
310
322
332
345
359
3628
370
380
390
401
412
423
437
4412
4536
460
470
480
491
502
513
525
5310
5416
5545
560
570
580
590
602
612
624
636
6412
6520
6655
670
680
690
700
711
723
733
746
758
7615
7725
7866
790
800
810
820

[0,0,1,0,0,3,0,1,1,6,0,0,1,2,10,0,0,1,2,4,15,0,0,
 1,1,4,6,21,0,0,0,2,2,5,9,28,0,0,0,1,2,3,7,12,36,0,
 0,0,1,2,3,5,10,16,45,0,0,0,0,2,2,4,6,12,20,55,0,0,
 0,0,1,3,3,6,8,15,25,66,0,0,0,0]