# [Prolog (SWI)], 55 bytes Y+X:-X=<Y;X mod Y>0,Y+1+X. \X:-X>1,2+X,- \X/\ \X=:=X+1. [Try it online!][TIO-l7mo7a6t] [Prolog (SWI)]: http://www.swi-prolog.org [TIO-l7mo7a6t]: https://tio.run/##KyjKz8lP1y0uz/z/P1I7wko3wtYm0jpCITc/RSHSzkAnUttQO0KPKwYkY2eoY6QdoaOrEBOhHwMkbK1sI7QN9f7/jzHS4@KKMQQRRgYg0hTMNjMGkRACLGBhaAmiMxJzSvQA "Prolog (SWI) – Try It Online"