A python snippet that will calculate a geometric sequence for you.

geo_sequence.py

t1 = int(input("Enter the first term (t1): "))
tn = int(input("Enter the final term (tn): "))
diff = int(input("Enter the spaces in between: "))

r = ( tn/t1 )**(1/(diff+1))

print("R is "+str(r));
print("t1 is "+str(t1));
print("tn is "+str(tn));

for i in range(1, diff+3):
    print(str(i) +": " + str(t1*r**(i-1)))