text: 1st post :) need help finding a formual? alright..story problem consists of building a path of blocks 1 ft. by 2 ft. the ending path should be 20 feet long, but with the rectangular blocks, [may need to draw picture] you can put them widthwise (makes path 1 foot longer, while still being 2 feet wide) or lengthwise (two blocks together, also making the path 2 feet wide, but is now 2 feet long.) the goal is to see how many different combinations you can make for 20 ft. path. you make a x,y table, (x rep. the length of the path in feet, and y is the number of combos you can make with the blocks) so..x: 1,2,3,4,5,6,7..etc. while y:1,2,3,5,8,13,21,55,76 (you can se the pattern is adding the first 2 y values to get the third ex 1+2=3; 3+5=8 ..etc.) now the hard part is finding a working formula where you can take any x value and plug it in to get the correct value of y...so far all i've seen is that the area of the path is 2(x) and that the x value is the number of blocks used in the combination..any ideas for a formula? thank you! looks somewhat like a diophantine problem...  a diophantine equation is an equation in which only integer solutions are allowed.