[3]n=4のとき
P0P1=P1P2=P2P3=P3P4=2
P0P2=P1P3=P2P4=√6
P0P3=P1P4=√6
P0P4=2
P0からでる最長辺はP0P2,P0P3の2本ある.
求めたい点はP0を含まないP2P3の中点ではなかろうか?
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P0(0,0,0,0,0)
P1(-4/5,1/5,1/5,1/5,1/5)
P2(-3/5,-3/5,2/5,2/5,2/5)
P3(-2/5,-2/5,-2/5,3/5,3/5)
P4(-1/5,-1/5,-1/5,-1/5,4/5)
P0P2^2=30/25=6/5
M(-1/2,-1/2,0,1/2,1/2)
P0M^2=1
一方,
[2]nが偶数のとき
(R/ρ)^2=n(n+2)/2(n+1)=24/10 (NG)
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