Function: primecertexport
Section: number_theoretical
C-Name: primecertexport
Prototype: GD0,L,
Help: primecertexport(cert,{format=0}): Returns a string suitable for
 print/write to display a primality certificate.
Doc:
 Returns a string suitable for print/write to display a primality certificate
 from \tet{primecert}, the format of which depends on the value of \kbd{format}:

 \item 0 (default): Human-readable format. See \kbd{??primecert} for the
 meaning of the successive $N, t, s, a, m, q, E, P$. The integer $D$ is the
 negative fundamental discriminant \kbd{coredisc}$(t^{2} - 4N)$.

 \item 1: Primo format 4.

 \item 2: MAGMA format.

 Currently, only ECPP Primality Certificates are supported.

 \bprog
 ? cert = primecert(10^35+69);
 ? s = primecertexport(cert); \\ Human-readable
 ? print(s)
 [1]
  N = 100000000000000000000000000000000069
  t = 546867911035452074
  s = 2963504668391148
 a = 0
 D = -3
 m = 99999999999999999453132088964547996
 q = 33743830764501150277
 E = [0, 1]
 P = [21567861682493263464353543707814204,
 49167839501923147849639425291163552]
 [2]
  N = 33743830764501150277
  t = -11610830419
  s = 734208843
 a = 0
 D = -3
 m = 33743830776111980697
 q = 45959444779
 E = [0, 25895956964997806805]
 P = [29257172487394218479, 3678591960085668324]

 \\ Primo format
 ? s = primecertexport(cert,1); write("cert.out", s);

 \\ Magma format, write to file
 ? s = primecertexport(cert,2); write("cert.m", s);

 ? cert = primecert(10^35+69, 1); \\ N-1 certificate
 ? primecertexport(cert)
  ***   at top-level: primecertexport(cert)
  ***                 ^---------------------
  *** primecertexport: sorry, N-1 certificate is not yet implemented.
 @eprog
