Cada terme de la successió de Fibonacci es calcula amb la suma dels dos anteriors. Si comencem com a dos primers l'1 i el 2, els primers 10 termes són: 1,2,3,5,8,3,21,34,55,89, ... Si ara considerem els termes de la successió de Fibonacci més petits que 4 milions, troba la suma dels termes parells.data:image/png;base64,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:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAeAAAAFoCAYAAACPNyggAAACtUlEQVR4nO3BMQEAAADCoPVPbQwfoAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA+Bo3+AAF/RMkcAAAAAElFTkSuQmCC5702887352457857028874613732