wonderful Demlo number

The initially palindromic numbers 1, 121, 12321, 1234321, 123454321, ... (OEIS A002477). For the first through ninth terms, the sequence is given by the generating function -(10x + 1)/((x - 1)(10x - 1)(100x - 1)) = 1 + 121x + 12321x^2 + 1234321x^3 + ... (Plouffe 1992, Sloane and Plouffe 1995). The definition of this sequence is slightly ambiguous from the tenth term on, but the most common convention follows from the following observation.

consecutive number sequences | palindromic number | repunit