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a(1) = a(2) = 1; a(n) = <rev>(a(n-1)) + <rev>(a(n-2)) for n > 2, where <rev>(k) denotes the concatenation of k with its reversal.
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%I #2 Feb 11 2014 19:05:28

%S 1,1,22,2233,22335544,2233554466886644,

%T 22335544668866446700441089106644,

%U 2233554466886644670044108910664466995742683267208933773289106644

%N a(1) = a(2) = 1; a(n) = <rev>(a(n-1)) + <rev>(a(n-2)) for n > 2, where <rev>(k) denotes the concatenation of k with its reversal.

%e a(5) = <>(a(4)) + <>(a(3)) = <>(2233) + <>(22) = 22333322 + 2222= 22335544.

%K base,nonn

%O 1,3

%A _Joseph L. Pe_, Apr 12 2002