It's hard but easy

$\large \sum { { ({ s }_{ i }+{ s }_{ k }) }^{ 3 } }$

$N$ is natural number such that ${ 2 }^{ n }|N$ for some whole number $n$ .Let ${ s }_{ a }$ be defined as a number formed from last $a+1$ digits on $N$ .Then find value of above expression modulo ${ 2 }^{ n }$ if $n-1\le i,k<j$ and $n+2<j$ .

Details:

$1)$ If $N=123456$ then number ${ s }_{ 3 }$ is $3456$ .

$2)$ $j$ is number of digits of $N$ .

This is an original problem.