"ARITHMETIC PROGRESSION. A sequence of numbers in which any number, or term, after the first can be obtained by adding a fixed number COMMDIFF to its predecessor. Example 12, 22, 32, 42... or 27, 25, 23, 21... Tosolve for progression enter any two term positions INDEX#A and INDEX#B and theirvalues TERM#A and TERM#B. TERM#N is the value for any index N and SUM is the sumof the progression up to and including term N. Type (F2) to return to helpfile."
