数論的関数
トゥエ=モース数列 a ( n ) = ( − 1 ) e 2 ( 1 ; n ) {\displaystyle a(n)=(-1)^{e_{2}(1;n)}}
product of digits 関数 p q ( n ) = ∏ j = 0 r b j ( n ) ( b r ( n ) ≠ 0 , b j ( n ) = 0 ( j > r ) ) {\displaystyle \textstyle p_{q}(n)=\prod _{j=0}^{r}b_{j}(n)\ \ \ \ \ (b_{r}(n)\neq 0,\ b_{j}(n)=0\ (j>r))}