OFFSET
1,1
COMMENTS
These numbers do not occur as differences between successive terms in A121805.
LINKS
Carlos Rivera, Puzzle 980. The "Commas" sequence, The Prime Puzzles and Problems Connection.
MATHEMATICA
a[1] = 1; a[n_] := a[n] = For[r = Mod[a[n - 1], 10]; y = 0, y <= 9, y++, If[y == IntegerDigits[#][[1]], Return[#]] &[a[n - 1] + 10 r + y]]; Complement[Range[99], Union@ Differences@ Array[a, 10^6]] (* Michael De Vlieger, Nov 18 2023, after Jean-François Alcover at A121805 *)
CROSSREFS
KEYWORD
nonn,base,fini,full
AUTHOR
N. J. A. Sloane, Nov 17 2023
STATUS
approved