fact: Definition rqs_Y rq1 rq3 (qs : rqseq) q1' : rqseq := let: RingQuestion k1 a1 _ := rq1 in let: RingQuestion k3 a3 q3 := rq3 in [:: RingQuestion k1 a1.+1 q1', RingQuestion k3 a3.+1 q3 & qs].
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype path fingraph) fourcolor(hypermap geometry color coloring patch cfmap quiz)