1,2

The last term is a(462331) = 987654321.

Observation: the number of terms mentioned above is also A014145(9). Also the sum of the 9th row in the triangle A288777.

It appears that the number of terms with k digits in this sequence is also A288777(9,k), k>=1.

Table of n, a(n) for n=1..67.

Subsequence of A215014.

Supersequence of A138141.

Cf. A014145, A033075, A288777.

Sequence in context: A097569 A308561 A095160 * A200372 A059043 A259236

Adjacent sequences: A288525 A288526 A288527 * A288529 A288530 A288531

nonn,base,easy,fini

Omar E. Pol, Jun 15 2017

approved