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”).

A133143 as a simple table

na(n)
11
21
31
42
54
64
75
86
98
1010
1111
1212
1313
1414
1515
1616
1717
1818
1919
2020

[1,1,1,2,4,4,5,6,8,10,11,12,13,14,15,16,17,18,19,
 20]