# [Haskell], <s>84 83</s> 67 bytes <!-- language-all: lang-hs --> z=zipWith e=[]:e f l=foldr(\_->z(z(+))l.foldr(z(:).reverse)e)l"123" [Try it online!][TIO-jcowbbzp] [Haskell]: https://www.haskell.org/ [TIO-jcowbbzp]: https://tio.run/##bVBNT4NAED27v2LkBBEb9qOtNMGD1xp70KQH3NgmXYS4/QhQbfnzCLvYXah7mMB7b968mXRdfAkp67qKquywzMoUiSjmM4ESkFGyl5vcff@4f6zcyr3zPDnSUOXOvFEuvkVeCE940sGEOvVpVaT7o9w8idUZIjgcy9cyf97BtvhENz@pyEX72TBZAqcoOkOZih04i/nIASELAc7L4g0W81sHoe062zXKzR4QNC@BOMacg5nQAIxzZFgfKPfVb/Ni4gMb6nEAPgAOLNkFsp1Yi8FE1ani2aUlVjAmqlJdByQoEuhgWDxWMLb6ydVGSkPVUKJisLEx0AgNrDo1rO6yWWLF1s6dw7Rzvl5aRx/r6Box12rO9aCw0Oyg94HQVlGL0FZ4cMXWSqlIYF25s7VVvRnGECbDy@nNiNJQpWd4cIP2CpqxVaHu6@XHhtcB/5BetPB/L9ZXMZOlcwy7XBzVvw "Haskell – Try It Online" Thanks to [Laikoni](https://codegolf.stackexchange.com/users/56433/laikoni) and [totallyhuman](https://codegolf.stackexchange.com/users/68615/totallyhuman) for saving a lot of bytes!