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koteitan @koteitan

B_0&=&(S_{r0},S_{r1})(S_{(r+1)0},S_{(r+1)1})\cdots (S_{(k-1)0},S_{(k-1)1})\\
B_k&=&(S_{r0}+k\Delta,S_{r1})(S_{(r+1)0}+k\Delta,S_{(r+1)1})\cdots (S_{(k-1)0}+k\Delta,S_{(k-1)1})\\
r &=& P_0(k)~(\mathrm{if}~ S_{k1}=0)\\
r &=& P_1(k)~(\mathrm{otherwise})\\
P_0(k)&=&\max_{j}\{ S_{j0} \lt S_{k0} \land j\lt k\}\\
P_1(k)&=&\max_{j}\{ S_{j0} \lt S_{k0} \land j\lt k~\land \exists a( j=P_0^a(k))\}\\
上記 K を「幻想○ア数列数」と定義します。