A plane partition whose solid Ferrers diagram is invariant under the rotation which cyclically permutes the x-, y-, and z-axes. Macdonald's plane partition conjecture gives a formula for the number of cyclically symmetric plane partitions (CSPPs) of a given integer whose Ferrers diagrams fit inside an n×n×n box. Macdonald gave a product representation for the power series whose coefficients q^n were the number of such partitions of n.

Macdonald's plane partition conjecture | magog triangle | plane partition