OFFSET
1,2
EXAMPLE
The 14th even digit of S is 4 (from 40) and this 4 is present in the 14th term of S (which is 24).
MATHEMATICA
a[1]=0; a[n_]:=a[n]=Block[{k=1}, While[MemberQ[l=Array[a, n-1], k]||FreeQ[IntegerDigits@k, Quiet@Select[Flatten[IntegerDigits/@Join[l, {k}]], EvenQ][[n]]], k++]; k]; Array[a, 75] (* Giorgos Kalogeropoulos, May 11 2022 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Eric Angelini and Carole Dubois, May 19 2021
STATUS
approved