Infinite sequences and gradients

[MathGuy]

I was wondering if anyone could point me to a program that calculated infinite sequences for expressions? If I for example wanted the sequence for arctan(x) the program should have the serie or sequence as output.

Can anyone also point me to a good program that can calculate gradients for functions?

[MathGuy]

Oh yeah and anything about lagrange multipliers would be great as well

[bostonvaulter]

maybe http://education.ti.com/educationportal/sites/US/productDetail/us_calctools_89.html

Calc tools has something for vector gradients, but I've never used it.

Sorry, i don't know anything for lagrange multipliers, and i don't really understand what you want for sequences.