The year’s biggest color trend wasn’t a single hue, at all. It was a blend of them. More precisely, it was ombré---the ten dollar word for color gradients.

Ronny Luss, Marc Teboulle, Conditional Gradient Algorithms for Rank-One Matrix Approximations with a Sparsity Constraint, SIAM Review, Vol. 55, No. 1 (March 2013), pp. 65-98 ...