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Jul 7, 2021 at 9:08 vote accept user70925
Jul 6, 2021 at 14:32 comment added Max Alekseyev @PeterTaylor: Indeed, I was about to make the same correction :)
Jul 6, 2021 at 14:30 comment added Peter Taylor @MaxAlekseyev, oh dear, I have made a mess of that comment. I copied the wrong part of my workings out: it should read $3s + 8t + 15u + 24v + \cdots = n-1$.
Jul 6, 2021 at 12:16 answer added Max Alekseyev timeline score: 3
Jul 6, 2021 at 11:54 history edited user70925 CC BY-SA 4.0
edited title
Jul 6, 2021 at 10:13 comment added Peter Taylor Apologies, I seem to have lost a reciprocal along the way. Change $n2^{-n}$ to $n^{-1} 2^{-n}$.
Jul 6, 2021 at 9:18 comment added მამუკა ჯიბლაძე To avoid confusion it would be better to call it reversion rather than inversion (the latter can be more likely understood as multiplicative inverse).
Jul 6, 2021 at 7:47 comment added Peter Taylor With a bit of simplification, $$A_n = n2^{-n} \sum_{s,t,u,\ldots} (-1)^{s+t+u+\cdots} \binom{n-1+s+t+u+\cdots}{s,t,u,\ldots}$$ where the sum is over non-negative integer solutions to $s + 2t + 3u + \cdots = n-1$.
Jul 6, 2021 at 7:38 comment added Peter Taylor Morse-Feshbach (see bottom of page) gives a sum over partitions of $n-1$ into numbers one less than a square; it's not a closed form or an elegant recurrence, but if your concern is practical evaluation then it may be of interest.
Jul 6, 2021 at 7:36 history edited user70925 CC BY-SA 4.0
added 33 characters in body
Jul 6, 2021 at 7:35 comment added user70925 Yes, indeed, it's exactly the same problem.
S Jul 6, 2021 at 1:49 history suggested Somos CC BY-SA 4.0
Fixed obvious typo.
Jul 6, 2021 at 1:29 review Suggested edits
S Jul 6, 2021 at 1:49
Jul 5, 2021 at 18:00 comment added F. C. By closely related, one should understand related by the substitution $q \mapsto q/2$.
Jul 5, 2021 at 17:06 history asked user70925 CC BY-SA 4.0