FUNCTION : _etanm - symbolic form eta[n,m](tau) CALLING SEQUENCE : _etanm(n,m) PARAMETERS : n,m - positive integers SYNOPSIS : _etanm(n,m) returns eta[n,m](tau) EXAMPLES : > with(thetaids): > _etanm(5,1); eta[5, 1](tau) SEE ALSO : _ETAnm, _ETAn, _etan