A126863 S(1)={1}. S(n) = {S(n-1) {1,2,...,(n-1),n,(n-1),...,2,1} S(n-1)}, where S(n) is a string of the first 3*2^n -2*n -3 terms of the sequence.

1, 1, 2, 1, 1, 1, 2, 3, 2, 1, 1, 1, 2, 1, 1, 1, 2, 3, 4, 3, 2, 1, 1, 1, 2, 1, 1, 1, 2, 3, 2, 1, 1, 1, 2, 1, 1, 1, 2, 3, 4, 5, 4, 3, 2, 1, 1, 1, 2, 1, 1, 1, 2, 3, 2, 1, 1, 1, 2, 1, 1, 1, 2, 3, 4, 3, 2, 1, 1, 1, 2, 1, 1, 1, 2, 3, 2, 1, 1, 1, 2, 1, 1, 1, 2, 3, 4, 5, 6, 5, 4, 3, 2, 1, 1, 1, 2, 1, 1, 1, 2, 3, 2, 1, 1

Offset

1,3

Comments

S(n) consists of the first 3*2^n - 2*n - 3 terms of the sequence, i.e. S(n) consists of A050488(n) terms.

Each S(n) forms a palindrome.

Links

Table of n, a(n) for n=1..105.

Example

S(1) = {1}.
S(2) = {1,1,2,1,1}.
S(3) = {1,1,2,1,1,1,2,3,2,1,1,1,2,1,1}.
S(4) = {1,1,2,1,1,1,2,3,2,1,1,1,2,1,1,1,2,3,4,3,2,1,1,1,2,1,1,1,2,3,2,1,1,1,2,1,1},
etc.

Crossrefs

Cf. A050488.

Sequence in context: A088863 A053283 A035669 * A106806 A178526 A039958

Adjacent sequences: A126860 A126861 A126862 * A126864 A126865 A126866

Keyword

easy,nonn

Author

Leroy Quet, Mar 15 2007

Status

approved