Function: zetamultconvert
Section: transcendental
C-Name: zetamultconvert
Prototype: GD1,L,
Help: zetamultconvert(a,{flag=1}): a being either an evec, avec, or index m,
 converts into evec (flag=0), avec (flag=1), or index m (flag=2).
Doc: \kbd{a} being either an \kbd{evec}, \kbd{avec}, or index \kbd{m},
 converts into \kbd{evec} ($\fl=0$), \kbd{avec} ($\fl=1$), or
 index \kbd{m} ($\fl=2$).
 \bprog
 ? zetamultconvert(10)
 %1 = Vecsmall([3, 2])
 ? zetamultconvert(13)
 %2 = Vecsmall([2, 2, 1])
 ? zetamultconvert(10, 0)
 %3 = Vecsmall([0, 0, 1, 0, 1])
 ? zetamultconvert(13, 0)
 %4 = Vecsmall([0, 1, 0, 1, 1])
 @eprog\noindent The last two lines imply that $[3,2]$ and $[2,2,1]$
 are dual (reverse order of bits and swap $0$ and $1$ in \kbd{evec} form).
 Hence they have the same zeta value:
 \bprog
 ? zetamult([3,2])
 %5 = 0.22881039760335375976874614894168879193
 ? zetamult([2,2,1])
 %6 = 0.22881039760335375976874614894168879193
 @eprog
