go =>
   % Integers 1..K
   N = 3,
   K = 5,
   printf("comb1(3,5): %w\n", comb1(N,K)),
   nl.

% Recursive (numbers)
comb1(M,N) = comb1_(M, 1..N).
comb1_(0, _X)     = [[]].
comb1_(_M, [])    = [].
comb1_(M, [X|Xs]) = [ [X] ++ Xs2 : Xs2 in comb1_(M-1, Xs) ] ++ comb1_(M, Xs).