A173529 a(n) = 1 + A053830(n-1), where A053830 is the sum of the digits of its argument in base 9.

1, 2, 3, 4, 5, 6, 7, 8, 9, 2, 3, 4, 5, 6, 7, 8, 9, 10, 3, 4, 5, 6, 7, 8, 9, 10, 11, 4, 5, 6, 7, 8, 9, 10, 11, 12, 5, 6, 7, 8, 9, 10, 11, 12, 13, 6, 7, 8, 9, 10, 11, 12, 13, 14, 7, 8, 9, 10, 11, 12, 13, 14, 15, 8, 9, 10, 11, 12, 13, 14, 15, 16, 9, 10, 11, 12, 13, 14, 15, 16, 17, 2, 3, 4, 5, 6, 7, 8, 9, 10, 3, 4, 5, 6, 7, 8, 9, 10, 11, 4

Offset: 1

Author

Omar E. Pol, Feb 23 2010

Keywords

• nonn
• base

Comments

If A053830 is regarded as a triangle then the rows converge to this sequence.

This is the case b=9 of a non-periodic sequence, with key formulas and definitions provided with b=5 in A173525. Case b=2 is in A063787, and cases b=3 to 8 are in A173523 to A173528.

Crossrefs

Cf. A000120, A053830, A063787, A173523, A173524, A173525, A173526, A173527, A173528.

Programs

Mathematica

Table[1 + Plus@@IntegerDigits[n - 1, 9], {n, 90}] (* Vincenzo Librandi, Jul 01 2019 *)

Formula

a(n) = A053830(9^k + n - 1) where k >= ceiling(log_9(n/8)). - R. J. Mathar, Dec 09 2010