Abstract
We show that there is a close relation between standing-wave solutions for the FitzHugh-Nagumo system
![](http://media.springernature.com/full/springer-static/image/art%3A10.1007%2Fs00209-006-0952-8/MediaObjects/s00209-006-0952-8flb1.gif)
where 0<a<1/2 and δ γ=β 2 ∈ (0,a), and the following combinatorial problem:
(*) Given K points Q 1 , . . . , Q K ∈R N with minimum distance 1, find out the maximum number of times that the minimum distance 1 can occur.
More precisely, we show that for any given positive integer K, there is a δ
K
>0 such that for 0<δ<δ
K
, there exists a standing-wave solution (u
δ
,ν
δ
) to the FitzHugh-Nagumo system with the property that u
δ
has K spikes Q
δ
1,. . .,Q
δ
K and approaches an optimal configuration in (*), where
.
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Wei, J., Winter, M. Standing waves in the FitzHugh-Nagumo system and a problem in combinatorial geometry. Math. Z. 254, 359–383 (2006). https://doi.org/10.1007/s00209-006-0952-8
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DOI: https://doi.org/10.1007/s00209-006-0952-8