Symbolic computation of F and G series by computer
Pasquale Sconzo, A. R. Leschack, Robert G. Tobey · The Astronomical Journal · 1965
A digital computer program (FORMAC) capable of generating and manipulating symbolic mathematical expressions has been used to derive explicit expressions for the coefficients of the f and g series of Keplerian motion. Terms up to the 27th order have been obtained as polynomials in the local invariants,', a, and E used by Stumpff.