OFFSET
1,1
COMMENTS
The multi-digit repdigits (A014181) are a subsequence. No term contains the digit 0 (zero). All terms containing digits 1 (one), 8 (eight), or 9 (nine) are also terms of A014181. Any term not mentioned above is a string of 2's (twos) and 3's (threes) only (a multi-digit term of A032810), 4's (fours) and 5's (fives) only, or 6's (sixes) and 7's (sevens) only.
EXAMPLE
454 is a term as digits "four", "five", "four" each begin with the letter "f".
CROSSREFS
KEYWORD
base,easy,nonn,word
AUTHOR
Rick L. Shepherd, Oct 19 2009
STATUS
approved