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A178664
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2^n concatenated with itself.
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4
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11, 22, 44, 88, 1616, 3232, 6464, 128128, 256256, 512512, 10241024, 20482048, 40964096, 81928192, 1638416384, 3276832768, 6553665536, 131072131072, 262144262144, 524288524288, 10485761048576, 20971522097152, 41943044194304
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OFFSET
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0,1
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COMMENTS
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a(1)=22 because 2^1 concatenated with 2^1 is 22.
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LINKS
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FORMULA
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MATHEMATICA
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Table[FromDigits[Join[IntegerDigits[2^n], IntegerDigits[2^n]]], {n, 0, 30}] (* Vincenzo Librandi, Mar 14 2012 *)
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PROG
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(Magma) [Seqint(Intseq(2^n) cat Intseq(2^n)): n in [0..40]]; // Vincenzo Librandi, Mar 14 2012
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CROSSREFS
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KEYWORD
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nonn,easy,base
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AUTHOR
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STATUS
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approved
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