■学会にて(京大数理解析研,その28)
continuant K(a1,a2,・・・,an)=1/[0;a1,a2,・・・,an]
K(a1)=a1
K(a1,a2)=a1a2+1
K(a1,a2,a3)=a1a2a3+a1+a3
K(a1,a2,・・・,an)=anK(a1,a2,・・・,an-1)+K(a1,a2,・・・,an-2)
===================================
K(a1,a2,・・・,an)=K(an,an-1,・・・,a1)
K(a1,a2,・・・,an)=amK(a1,a2,・・・,am)K(am+1,・・・,an)+K(a1,a2,・・・,am-1)K(am+2,・・・,an)
===================================