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Problem 6 was surprisingly straight-forward.

“Find the difference between the sum of the squares of the first one hundred natural numbers and the square of the sum.”

Really, just a straight-forward calculation, easily implemented in Erlang recursive-speak. No real comments on this one.

-module(euler6).
 -export([difference/1]).

 difference(N) ->
    SumSquare = sumofsquares(0,N),
    Sum = squareofsum(0,N),
    SquareSum = Sum * Sum,
    io:format("Square ~w Sum ~w ~n", [SquareSum, SumSquare]),
    Difference = SquareSum - SumSquare,
    Difference.  

sumofsquares(Sum,N) ->
    if N >= 1 ->
       NewSum = (N*N) + sumofsquares(Sum,N-1);
    true ->
       NewSum = Sum
    end,
    NewSum.

squareofsum(Sum, N) ->
     if N >= 1 ->
       NewSum =  N + squareofsum(Sum, N-1);
     true ->
       NewSum = 0
      end,
     NewSum.