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About: About this document makeUsp4
Procedure from library ncalg.lib (see ncalg_lib).

makeUsp4([p]); p an optional integer (field characteristic)

a ring, describing U(sp_4)

You have to activate this ring with the 'setring' command. The presentation of U(sp_4) is derived from the Chevalley representation of sp_4, positive resp. negative roots are denoted by x(i) resp. y(i); Cartan elements are denoted by h(i).

LIB "ncalg.lib";
def ncAlgebra = makeUsp4();
==> //   characteristic : 0
==> //   number of vars : 36
==> //        block   1 : ordering dp
==> //                  : names    X(1) X(2) X(3) X(4) X(5) X(6) X(7) X(8) X(\
   9) X(10) X(11) X(12) X(13) X(14) X(15) X(16) Y(1) Y(2) Y(3) Y(4) Y(5) Y(6\
   ) Y(7) Y(8) Y(9) Y(10) Y(11) Y(12) Y(13) Y(14) Y(15) Y(16) H(1) H(2) H(3)\
==> //        block   2 : ordering C
==> //   noncommutative relations: ...
setring ncAlgebra;
// ...  264  noncommutative relations
See also: makeUe6; makeUe7; makeUe8; makeUf4; makeUg2; makeUsl; makeUso5; makeUsp1.