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A273092
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a(n) = 2^n - 1 written backwards.
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1
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0, 1, 3, 7, 51, 13, 36, 721, 552, 115, 3201, 7402, 5904, 1918, 38361, 76723, 53556, 170131, 341262, 782425, 5758401, 1517902, 3034914, 7068838, 51277761, 13445533, 36880176, 727712431, 554534862, 119078635, 3281473701, 7463847412, 5927694924, 1954399858
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OFFSET
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0,3
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COMMENTS
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Reverse primes in this sequence (3, 7, 31, 127, 2047, 8191, 131071, 524287, 8388607 etc) are Mersenne primes.
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LINKS
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FORMULA
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EXAMPLE
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For n = 8, 2^n - 1 = 255, so 552 is in the sequence. - Michael B. Porter, Jul 02 2016
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MATHEMATICA
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Table[FromDigits[Reverse[IntegerDigits[2^n-1]]], {n, 0, 75}]
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PROG
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(Magma) [Seqint(Reverse(Intseq(2^n-1))): n in [0..40]];
(PARI) a(n) = eval(concat(Vecrev(Str(2^n-1)))) \\ Felix Fröhlich, Jul 03 2016
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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STATUS
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approved
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