>>187
いいえ。

 (1/6)π^2 = ζ(2)
 = Σ[k=1,∞) 1/k^2
 = Σ[k=1,n] 1/k^2 + Σ[k=n+1,∞) 1/k^2
 < Σ[k=1,n] 1/k^2 + Σ[k=n+1,∞) 1/(k^2 -1/4)
 = Σ[k=1,n] 1/k^2 + Σ[k=n+1,∞) {1/(k -1/2) - 1/(k +1/2)}
 = Σ[k=1,n] 1/k^2 + 1/(n + 1/2)
 = 1 + 1/4 + 1/9 + 1/16 + 2/9  (← n=4 とおく)
 = 5/3 - 1/48
< 5/3 - 1/49
 = (1/6)(22/7)^2,

∴ π < 22/7,