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”).

A237047 as a simple table

na(n)
00
1-1
2-2
3-4
4-6
5-8
6-8
70
828
9102
10280
11680
121544
133368
147152
1514912
1630706
1762672
18127124
19256744
20516952
211038672
222083864
234176576
248365080
2516746150
2633513608
2767055456
28134148160
29268345208
30536754288
311073591680
322147291036
334294721040
348589620784

[0,-1,-2,-4,-6,-8,-8,0,28,102,280,680,1544,3368,
 7152,14912,30706,62672,127124,256744,516952,
 1038672,2083864,4176576,8365080,16746150,33513608,
 67055456,134148160,268345208,536754288,1073591680,
 2147291036,4294721040,8589620784]