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A036447
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Double and reverse digits.
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21
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1, 2, 4, 8, 61, 221, 244, 884, 8671, 24371, 24784, 86594, 881371, 2472671, 2435494, 8890784, 86518771, 245730371, 247064194, 883821494, 8892467671, 24353948771, 24579870784, 86514795194, 883095920371, 2470481916671, 2433383690494
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OFFSET
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0,2
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LINKS
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FORMULA
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MATHEMATICA
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NestList[ FromDigits[ Reverse[ IntegerDigits[ 2# ] ] ] &, 1, 27 ]
NestList[IntegerReverse[2#]&, 1, 30] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 18 2017 *)
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PROG
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(Haskell)
a036447 n = a036447_list !! n
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CROSSREFS
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The following are parallel families: A000079 (2^n), A004094 (2^n reversed), A028909 (2^n sorted up), A028910 (2^n sorted down), A036447 (double and reverse), A057615 (double and sort up), A263451 (double and sort down); A000244 (3^n), A004167 (3^n reversed), A321540 (3^n sorted up), A321539 (3^n sorted down), A163632 (triple and reverse), A321542 (triple and sort up), A321541 (triple and sort down).
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KEYWORD
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nonn,base,easy,nice
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AUTHOR
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EXTENSIONS
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More terms from Larry Reeves (larryr(AT)acm.org), Mar 31 2000
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STATUS
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approved
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