"""
Created on: Tue Nov 16 13:23:01 2021
Author: vila@cs.upc.edu
"""
def gseries_conv(a, r, d):
    # INI
    suma = 0.0 # sum
    i = 0 # number of summed t
    t = a # next term
    e = 1/10**d # tolerance
    
    while abs(t) >= e:
        # REPE
        suma += t
        i += 1
        t = t * r
    # FI
    return round(suma, 4), i