erich-friedman/erich-friedman.github.io

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Is Gensane & Ryckelynck's 11-square packing identical to the 1979 packing of Walter Trump?

Squares in squares on Wikipedia has this to say:

By contrast, the tightest known packing of 11 squares is inside a square of side length approximately 3.877084, slightly improving a similar packing found earlier by Walter Trump [[6]]

The reference pointing to Gensane, T., & Ryckelynck, P. (2004). Improved Dense Packings of Congruent Squares in a Square. Discrete & Computational Geometry, 34(1), 97–109.

Case n = 11. The best known packing is due to Trump and apparently to many other
people. In [3] we find that s11 ≤ 3.8772 for a packing given in Fig. 3. We have obtained
this packing several times with s11 = 3.87708359 . . ., a result which is slightly better.

Their reference 3 is the very familiar E. Friedman, Packing unit squares in squares: a survey and new results, Electron. J. Combin. 7 (2000), #DS7.

The online version of this paper does however list this as s(11)<3.8771 , different in the last digit from what Gensane & Ryckelynck quote.

Is this just a precision problem in the value originally published, or did Gensane & Ryckelynck find some distinct and subtly improved packing?

Primordial Soup Kitchen link is dead, could be replaced by Wayback Machine link

Hi Erich,

I hope all is well with you. You might want to replace the broken link to the Primordial Soup Kitchen with a Wayback Machine link.

The latest archived version link is https://web.archive.org/web/20210508205025/http://psoup.math.wisc.edu/kitchen.html , all later ones are "access denied".

Thanks again for all the interesting problems!
Ron