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”).

A221271 as a simple table

na(n)
10
216
30
4596
50
624366
70
81001855
90
1041171316
110
121691327788
130
1469470653170
150
162853337539621
170
18117191717993760
190
204813242705044572
210
22197686734633818238
230
248119268451165592095
250

[0,16,0,596,0,24366,0,1001855,0,41171316,0,
 1691327788,0,69470653170,0,2853337539621,0,
 117191717993760,0,4813242705044572,0,
 197686734633818238,0,8119268451165592095,0]