Well, now that I understand your intentions a little bit better (and having read through the other comments), I seriously want to second the recommendation of Scheme.
Use DrScheme as environment (zero-hassle), go through SICP and HTDP. Algorithms are nice, Knuthâs series and so, but it may be more than you are asking. Project Euler is a website where you can find some inspirations for problems you may want to solve. Scheme as a language has the advantages that you will not need time to wrap your head around ugly syntax (most languages, except for Lua, maybe Python), memory management (C), or mathematical purity (Haskell, Prolog). AFAIK they also distinguish between exact (rational numbers, limited only by RAM) and inexact numbers (floating points) -- regularly a confusion for people trying to do some numeric code the first time. The trade-offs are quite different for professional programmers, though.
Well, now that I understand your intentions a little bit better (and having read through the other comments), I seriously want to second the recommendation of Scheme.
Use DrScheme as environment (zero-hassle), go through SICP and HTDP. Algorithms are nice, Knuthâs series and so, but it may be more than you are asking. Project Euler is a website where you can find some inspirations for problems you may want to solve. Scheme as a language has the advantages that you will not need time to wrap your head around ugly syntax (most languages, except for Lua, maybe Python), memory management (C), or mathematical purity (Haskell, Prolog). AFAIK they also distinguish between exact (rational numbers, limited only by RAM) and inexact numbers (floating points) -- regularly a confusion for people trying to do some numeric code the first time. The trade-offs are quite different for professional programmers, though.
edit: welcome to the web, using links!