\\ Pari/GP code for working with number field 21.3.4297390112987454978404646912.1

\\ Some of these functions may take a long time to execute (this depends on the field).

\\ Define the number field: 
K = bnfinit(y^21 - y^20 + 9*y^19 - 7*y^18 + 35*y^17 - 27*y^16 + 83*y^15 - 61*y^14 + 123*y^13 - 111*y^12 + 163*y^11 - 225*y^10 + 213*y^9 - 253*y^8 + 177*y^7 - 167*y^6 + 192*y^5 - 180*y^4 + 136*y^3 - 76*y^2 - 12*y + 4, 1)

\\ Defining polynomial: 
K.pol

\\ Degree over Q: 
poldegree(K.pol)

\\ Signature: 
K.sign

\\ Discriminant: 
K.disc

\\ Ramified primes: 
factor(abs(K.disc))[,1]~

\\ Integral basis: 
K.zk

\\ Class group: 
K.clgp

\\ Unit rank: 
K.fu

\\ Generator for roots of unity: 
K.tu[2]

\\ Fundamental units: 
K.fu

\\ Regulator: 
K.reg

\\ Analytic class number formula: 
# self-contained Pari/GP code snippet to compute the analytic class number formula
K = bnfinit(x^21 - x^20 + 9*x^19 - 7*x^18 + 35*x^17 - 27*x^16 + 83*x^15 - 61*x^14 + 123*x^13 - 111*x^12 + 163*x^11 - 225*x^10 + 213*x^9 - 253*x^8 + 177*x^7 - 167*x^6 + 192*x^5 - 180*x^4 + 136*x^3 - 76*x^2 - 12*x + 4, 1);
[polcoeff (lfunrootres (lfuncreate (K))[1][1][2], -1), 2^K.r1 * (2*Pi)^K.r2 * K.reg * K.no / (K.tu[1] * sqrt (abs (K.disc)))]

\\ Intermediate fields: 
L = nfsubfields(K); L[2..length(b)]

\\ Galois group: 
polgalois(K.pol)

\\ Frobenius cycle types: 
\\ to obtain a list of $[e_i,f_i]$ for the factorization of the ideal $p\mathcal{O}_K$ for $p=7$ in Pari:
p = 7; pfac = idealprimedec(K, p); vector(length(pfac), j, [pfac[j][3], pfac[j][4]])