A317197 a(n) is the concatenation of A103269(n-i) for i = 0,1,2,...,n-1.

1, 121, 1213121, 12131211213121, 121312112131212131211213121, 121312112131212131211213121312112131212131211213121, 12131211213121213121121312131211213121213121121312112131212131211213121312112131212131211213121

Offset

1,2

Comments

a(n) is a palindrome.

A027084 gives lengths of these words.

Links

Table of n, a(n) for n=1..7.

Bo Tan and Zhi-Ying Wen, Some properties of the Tribonacci sequence, European Journal of Combinatorics, 28 (2007) 1703-1719. See D_n.

Example

a(3) = 1213.12.1 = 1213121.

Crossrefs

A027084.

Sequence in context: A261364 A317956 A136094 * A082215 A123179 A245593

Adjacent sequences: A317194 A317195 A317196 * A317198 A317199 A317200

Keyword

nonn

Author

N. J. A. Sloane, Aug 05 2018

Status

approved