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A101896
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Primes obtained if 2^j for some suitable j is written backward.
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1
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2, 61, 23, 821, 4201, 270131, 61277761, 274359834731, 23888027348153, 86936981079782063, 4243031147170261950811, 272838646828154727511151, 821882010875193363312928672952261, 274562423560500997742392394025368175422471, 4266472836315949449695828501889595072967427241
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OFFSET
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1,1
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COMMENTS
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The relevant exponents are collected in A057708.
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LINKS
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FORMULA
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EXAMPLE
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Reverse 128, obtain 821, a prime.
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MATHEMATICA
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Select[FromDigits@ Reverse@ IntegerDigits[2^#] & /@ Range@ 3200, PrimeQ] (* Michael De Vlieger, Dec 03 2015 *)
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PROG
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(GAP) a:=Filtered(List(List([1..300], j->Reversed(ListOfDigits(2^j))), k->Sum([1..Size(k)], i->k[i]*10^(Size(k)-i))), IsPrime);; Print(a); # Muniru A Asiru, Dec 25 2018
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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STATUS
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approved
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