Svaki zadatak ovog lanca će izgledati ovako:
Tako ćemo označavati ostatak pri dijeljenju broja 
s brojem 
. Na primjer, 
i 
.
Odredi:
Every task within this chain will look like this:
This is how we will denote the remainder when is divided by . For example, i .
Determine:
[lang=hr]
Svaki zadatak ovog lanca će izgledati ovako:
\begin{center} Odredi $A \pmod{B}$ gdje će $A$ i $B$ biti prirodni. \end{center}
Tako ćemo označavati ostatak pri dijeljenju broja $A$ s brojem $B$. Na primjer, $5 \pmod{2} = 1$ i $73 \pmod{10} = 3$. \\
Odredi:
\begin{center} $1 + 11 + 111 + 1111 + \dots + \underbrace{111\dots111}_{ \underbrace{11\dots11}_{111 \;\text{jedinica}} \;\text{jedinica} } \pmod{10^9}$ \end{center}
[/lang]
[lang=en]
Every task within this chain will look like this:
\begin{center} Determine $A \pmod{B}$ where $A$ and $B$ are positive integers. \end{center}
This is how we will denote the remainder when $A$ is divided by $B$. For example, $5 \pmod{2} = 1$ i $73 \pmod{10} = 3$. \\
Determine:
\begin{center} $1 + 11 + 111 + 1111 + \dots + \underbrace{111\dots111}_{ \underbrace{11\dots11}_{111 \;\text{ones}} \;\text{ones} } \pmod{10^9}$ \end{center}
[/lang]
gdje će 
