In "Base 27: the key to a New Gematria" in the May 1993 Word Ways, Lee Sallows offered "immortal fame" in finding doubly true equations (those valid in both base 10 and base 27 notion). I do not know where he obtained authority to grant such fame, but I accept his challenge.
"Doubly True Alphametics in Base 27,"
Word Ways: Vol. 31
, Article 20.
Retrieved from: https://digitalcommons.butler.edu/wordways/vol31/iss3/20