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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.
2

%I #8 Aug 25 2015 16:02:40

%S 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,

%T 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,

%U 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

%N 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.

%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 1).

%F a(1) = 1; for k > 0, a(3k-1) = a(3k) = 2; a(3k+1) = 3. - _David Wasserman_, Aug 19 2004

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

%t Join[{1},LinearRecurrence[{0, 0, 1},{2, 2, 3},104]] (* _Ray Chandler_, Aug 25 2015 *)

%Y Cf. A082205, A082206.

%K base,easy,nonn

%O 0,2

%A _Amarnath Murthy_, Apr 10 2003

%E More terms from _David Wasserman_, Aug 19 2004