fact: Definition nds_explicit C4 C5 C6 k i := Yo (i = \0c) (C5 ^c k) (Yo (i = \1c) (C6 *c C5 ^c (k -c \1c)) (Yo (i = \2c) (C6 ^c \2c *c C5 ^c (k -c \2c)) (Yo (i = \3c) (Yo (k = \1c) (C4 ^c \2c) (Yo (k = \2c) (C4 ^c \2c *c C5) (C6 ^c \3c *c C5 ^c (k -c \3c)))) (C4 *c C5 ^c k)))).
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat)