⊿_n = (右辺) - (左辺)
= (n-1)Σ[k=1,n] (a_k)^n - {Σ[k=1,n] a_k}{Σ[k=1,n] (a_k)^(n-1)} + n･a_1･a_2…a_n,
a_1 = a，a_2 = b，a_3 = c，a_4 = d，a_5 = e，
とおいてシューア展開すると、
⊿_1(a) = 0,
⊿_2(a,b) = 0,
⊿_3(a,b,c) = F_1(a,b,c)
⊿_4(a,b,c,d) = (2/3){F_2(a,b,c) + F_2(b,c,d) + F_2(c,d,a) + F_2(d,a,b)} + (1/3){F_1(a,b,c)d + F_1(b,c,d)a + F_1(c,d,a)b + F_1(d,a,b)c},
⊿_5(a,b,c,d,e) = (1/2)Σ[a,b,c] F_3(a,b,c) + (1/6)Σ[a,b,c] F_2(a,b,c)(d+e) + (1/6)Σ[a,b,c] F_1(a,b,c)de,
ここに Σ[a,b,c] は C[5,3] = 10項の和
