Into the 4th dimension
C_K_Yang ironman353 czp001 liuguangxi zimpha a_forsteri Min_25 C3PO Philippe_57721 mathpseudo sinan hervas benito255 lesnik7 nielkh
Public  09/01/17  5xp  Math  68.2% 
Consider a sphere whose square of its radius is $n$ and centered at $(0,0,0,0)$ in the $4^{th}$ dimension space.
For a given $n$, the sphere touches a certain number of integer lattice points.
For instance, if $n = 7$, it touches the point (1,2,1,1)
Let $t(n)$ the number of integer lattice points touched by the sphere with square of radius $n$
Find $\sum_{k=0}^{100}t(10^{17}+k)$
You are given $\sum_{k=0}^{100}t(1000+k)=1042664$
[My timing: 9 sec]
For a given $n$, the sphere touches a certain number of integer lattice points.
For instance, if $n = 7$, it touches the point (1,2,1,1)
Let $t(n)$ the number of integer lattice points touched by the sphere with square of radius $n$
Find $\sum_{k=0}^{100}t(10^{17}+k)$
You are given $\sum_{k=0}^{100}t(1000+k)=1042664$
[My timing: 9 sec]
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