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a(1) = 1. For n > 1, a(n) is the least unused number such that the concatenation a(n)a(n-1)...a(2)a(1) is prime.
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%I #5 Mar 30 2012 17:29:13

%S 1,3,4,5,7,14,9,6,57,13,18,17,16,12,20,82,42,21,45,78,98,33,133,50,28,

%T 41,124,36,44,19,80,40,75,63,372,168,179,85,84,128,64,302,151,248,10,

%U 69,123,11,54,31,149,34,185,51,213,43,282,105,125,237,55,174,96,438,215,61

%N a(1) = 1. For n > 1, a(n) is the least unused number such that the concatenation a(n)a(n-1)...a(2)a(1) is prime.

%C Is this a rearrangement of the natural numbers?

%Y Cf. A089710, A089711, A089561-A089573.

%K base,nonn

%O 1,2

%A _Ray Chandler_, Nov 22 2003

%E Edited by _Charles R Greathouse IV_, Apr 29 2010