20/01/13 00:43:42.92 JM7pXrDp.net
>>535
P_n(t) はn次の第一種チェビシェフ多項式
P_1(t) = t,
P_2(t) = 2t^2 -1,
P_3(t) = 4t^3 -3t,
P_4(t) = P2(P2(t)) = 8t^4 -8t^2 +1,
P_8(t) = P2(P2(P2(t))) = 128t^8 -256t^6 +160t^4 -32t^2 +1,
P_9(t) = P3(P3(t)) = 256t^9 -576t^7 +432t^5 -120t^3 +9