School themes from USSR and EurAsia

[Jack]

bplus, it would be interesting to have a program that would make it easy to explore sequences using the number wall system, I envision a graphic program where you could enter a sequence and you could either have the program run through the process or you would select 1 of 3 cursors, cross, big cross or horse shoe and then move the cursor on the sequence and click to have the program supply the missing number, it would also be useful if the program allowed you to click&drag to select say a square of numbers and the program would report whether the selected square's determinant is 0 or not, this is just for starters