OFFSET
1,3
COMMENTS
EXAMPLE
29 is a term because 2*9=18 and 1+8=9 and 29 contains digit 9.
MATHEMATICA
digRoot[n_] := If[n == 0, 0, Mod[n - 1, 9] + 1]; q[n_] := Module[{d = IntegerDigits[n]}, MemberQ[d, digRoot[Times @@ d]]]; Select[Range[0, 112], q] (* Amiram Eldar, Mar 11 2024 *)
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Saish S. Kambali, Mar 11 2024
STATUS
approved