#1:  " ----------[ D e r i v e ]---------- "                User


        #2:  " ---------- Initialization ---------- "               User


        #3:  " ---------- Combinatorial Theory ---------- "         User


        User

        #4:  " Pochhammer symbol (a)_n = a (a + 1) ... (a + n - 1) => a (a +

               1) (a + 2) "


        #5:  POCHHAMMER(a, 3)                                       User


        #6:  a*(a + 1)*(a + 2)                                  Simp(#5)


        #7:  " Binomial coefficient => n (n - 1) (n - 2)/6 "        User


        #8:  COMB(n, 3)                                             User


              n*(n - 1)*(n - 2) 
        #9:  -------------------                                Simp(#8)
                      6         


        #10: " 2^n n! (2 n - 1)!! => (2 n)! "                       User


        #11: "2^n * n! * (2*n - 1)!!"                               User


        #12: " 2^n n! product(2 k - 1, k = 1..n) => (2 n)! "        User


              n       n             
        #13: 2 *n!*PRODUCT (2*k - 1)                                User
                     k=1            


               2*n    /     1 \  
              2   *n!*|n - ---|! 
        #14:          \     2 /                                Simp(#13)
             --------------------
                   SQRT(pi)      


        User

        #15: " => (2 n)!/[2^(2 n) (n!)^2]   or   (2 n - 1)!!/[2^n n!] "


                   /     1 \ 
              GAMMA|n + ---| 
        #16:       \     2 /                                        User
             ----------------
                SQRT(pi)*n!  


               /     1 \  
               |n - ---|! 
        #17:   \     2 /                                       Simp(#16)
             -------------
              SQRT(pi)*n! 


        User

        #18: " Partitions of an integer => {1+1+1+1, 1+1+2, 1+3, 2+2, 4} (5

               in all) "


        #19: 4                                                      User


        #20: 4                                                 Simp(#19)


        #21: " Stirling numbers of the first kind: S_1(5, 2) => -50 "User


        #22: "stirling1(5, 2)"                                      User


        #23: " Euler's totient function => 576 "                    User


        #24: "totient(1776)"                                        User


        #25: " ---------- Quit ---------- "                         User