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a(n) is a number such that if odd positioned digits are deleted one gets n and if even positioned digits are deleted one gets n reversed. Counting is from the LSB side. The position of LSB is one.
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%I #11 Feb 14 2015 16:25:29

%S 11,22,33,44,55,66,77,88,99,1001,1111,1221,1331,1441,1551,1661,1771,

%T 1881,1991,2002,2112,2222,2332,2442,2552,2662,2772,2882,2992,3003,

%U 3113,3223,3333,3443,3553,3663,3773,3883,3993,4004,4114,4224,4334,4444,4554

%N a(n) is a number such that if odd positioned digits are deleted one gets n and if even positioned digits are deleted one gets n reversed. Counting is from the LSB side. The position of LSB is one.

%C Except for initial 0, rearrangement of numbers in A056524. They first differ at a(101) = 110011, while A056524(101) = 101101. If n has digits d_1 d_2 ... d_k, permute them to d_1 d_k d_2 d_{k-1} ... d_{floor(k/2)+1} and use that as index to A056524. - _Franklin T. Adams-Watters_, Jun 20 2006

%H Reinhard Zumkeller, <a href="/A110745/b110745.txt">Table of n, a(n) for n = 1..9999</a>

%e a(12) = 1221, deleting the LSB and the third digit 2 we get 12, deleting second and fourth digit we get 21.

%o (Haskell)

%o import Data.List (transpose)

%o a110745 n = read (concat $ transpose [ns, reverse ns]) :: Integer

%o where ns = show n

%o -- _Reinhard Zumkeller_, Feb 14 2015

%Y Cf. A045918.

%Y Cf. A056524, A031298.

%K base,nonn

%O 1,1

%A _Amarnath Murthy_, Aug 10 2005

%E More terms from _Franklin T. Adams-Watters_, Jun 20 2006