A082204 Begin with a 1, then place the smallest (as far as possible distinct) digits, such that, beginning from the n-th term, n terms form a palindrome.

1, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2

Offset

0,2

Links

Table of n, a(n) for n=0..104.

Index entries for linear recurrences with constant coefficients, signature (0, 0, 1).

Formula

a(1) = 1; for k > 0, a(3k-1) = a(3k) = 2; a(3k+1) = 3. - David Wasserman, Aug 19 2004

Example

The first six palindromes are 1, 22, 232, 3223, 22322, 232232.

Mathematica

Join[{1}, LinearRecurrence[{0, 0, 1}, {2, 2, 3}, 104]] (* Ray Chandler, Aug 25 2015 *)

Crossrefs

Cf. A082205, A082206.

Sequence in context: A261865 A003589 A361486 * A378914 A152727 A087159

Adjacent sequences: A082201 A082202 A082203 * A082205 A082206 A082207

Keyword

base,easy,nonn

Author

Amarnath Murthy, Apr 10 2003

Extensions

More terms from David Wasserman, Aug 19 2004

Status

approved