# Can you help, please. [closed]

I am anything else but a math geek so I am stunned by the following:

C<>7 ASCII

x(0)=0 x(n+1)=C(n) mod(Y/17)

y(0)=0 y(n+1)=y(n)+(C(n) mod(X/80))+1

What kind of calculation or equation is that? I am especially confused by the case change of x and y on the left to upper case on the right. Does this have a special meaning or is it just a mistake?

Sorry, but what does this have to do with Sage?

I agree. This looks like a difference equation to me. But it isn't a Sage question - you may want to try math.stackexchange.org, though I suggest giving a reference and more details if you want to ask someone.