Talk:Hofstadter sequence
 | This article is rated Start-class on Wikipedia's content assessment scale. It is of interest to the following WikiProjects: | ||||||||||
| |||||||||||
Claimed explicit formula for S(n)
[edit]In the Figure-Figure Sequence section there was a claim that an explicit formula for the sequence S(n) was given by
![{\displaystyle {\begin{aligned}S(n)&=1+2n-{\Bigg \lfloor }\sum _{i=1}^{n}{\frac {1}{\sqrt[{i}]{i}}}{\Bigg \rfloor }.\end{aligned}}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/95fa47e185fe15175d1ad4c16d9230773f4bd856)
I have removed this because it is incorrect. The claim first fails at n = 38, when S(38) = 46, but
![{\displaystyle 1+2\times 38-{\Bigg \lfloor }\sum _{i=1}^{38}{\frac {1}{\sqrt[{i}]{i}}}{\Bigg \rfloor }=77-\lfloor 32.0555\rfloor =45}](https://wikimedia.org/api/rest_v1/media/math/render/svg/da0e1978abc13d1d87849c287cca1af338b186fb)
Gandalf61 (talk) 10:00, 23 June 2011 (UTC)
- You're right of course. My apologies. Conchisness (talk) 11:46, 23 June 2011 (UTC)
Please check The Pinn generalization formula, it seems different from what appears to be the used one in the page you cite as a source: http://oeis.org/A055748
In particular, I think you switched two of the arguments: F(n - a(n-j) - 1) has become F(n - 1 - a(n-j)) — Preceding unsigned comment added by 87.14.26.44 (talk) 15:45, 2 November 2013 (UTC)