A171093 a(n) is the string of integers S(n) concatenated together with no commas, where S(1)=1; for even n, S(n) = S(n-1),n; and for odd n>1, S(n) is obtained by adding 1 to every entry of S(n-1) and appending 1.

1, 12, 231, 2314, 34251, 342516, 4536271, 45362718, 564738291, 56473829110, 6758493102111, 675849310211112, 78695104113122131, 7869510411312213114, 897106115124133142151, 89710611512413314215116

Offset

1,2

Links

Table of n, a(n) for n=1..16.

Micah Spencer Coleman, Asymptotic Enumeration in Pattern Avoidance and in the Theory of Set Partitions and Asymptotic Uniformity, Dissertation, 2018.

Mathematica

f[n_] := Block[{k, l}, If[ OddQ@ n, k = 2; l = {1}, k = 1; l = {}]; FromDigits@ Flatten@ Join[ Table[{IntegerDigits[ Floor[n/2] - j + k], IntegerDigits[n - Floor[n/2] + j]}, {j, Floor[n/2]}], l]]; Array[f, 16] (* Robert G. Wilson v, Sep 25 2010 *)

Crossrefs

Sequence in context: A231448 A221657 A089370 * A089343 A303487 A280071

Adjacent sequences: A171090 A171091 A171092 * A171094 A171095 A171096

Keyword

nonn,base,easy

Author

N. J. A. Sloane, Sep 18 2010

Extensions

a(7) onwards from Robert G. Wilson v, Sep 25 2010

Status

approved