SUMMARY:

a2bmodc(a,b,c)               -  Computes   a^b  mod(c)
chin(a,b,c,d)                   -  computes  [u, v]   such that
                                      n=u (mod v)    <=>   n=a (mod b) &  n=c (mod d)
                                      chin stands for   CHINESE
divisors(n)                     -   Produces the list of divisors of  n
     divisors2(n)
factor(n)                        -  factors  n
    factor2(n)
    factor3(n)
gcd(a,b)                         -  (The)  Greatest Common Divisor
                                             useful in solving   ax+by=1
                                             or    ax+by=gcd(a, b).
invmod(m,n)                   -  inverts  m  mod(n)
isprime                          -   test the vector entries for being prime
jac(p,q)                         -   computes  Jacobi  (Legendre)  symbol
                                               of  p  mod  q
lcm                               -   (The) Least  Common  Multiple
mindivisor(n)                -   Produces the minimal positive divisor of  n
                                             different from  1
mu(n)                            -   Mobius function    mu(n)
parents                         -   for  finding  Farey  parents
phi(n)                            -   Eulerıs function  phi(n)=card(U(n))
primes(n)                      -   Produces primes  < n
     primes2(n)
primenum(n)                  -   returns  n-th prime number
qrs(p)                            -  lists  QRs
tostr(x,m,n)                  -   Codes  x  into a string  Fortran style
                                                (m, n are optional)
t, tplus etc.                   - test replacement problem