FUNCTION :  _ETAn - a symbolic form for eta(n*tau) in terms of JAC

CALLING SEQUENCE :  _ETAn(n)                                                
                    

PARAMETERS :      n  - positive integer

SYNOPSIS :  _ETAn(n) returns q^(n/24)*JAC(0,n,infinity) which is a  
            symbolic form for eta(n*tau)

EXAMPLES :   


> _ETAn(10);
                          (5/12)
                         q       JAC(0, 10, infinity)

DISCUSSION :

eta(10tau) = q^(5/12)*JAC(0,10,infinity)

SEE ALSO :  

_ETAnm,
_etan,
_etanm