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 A054256 Concatenation of n in base 2 up to base 10 is prime, all numbers are interpreted as decimals. 3

%I

%S 7,33,169,197,209,351,401,419,459,541,553,599,883,971,981,1081,1107,

%T 1201,1351,1363,2011,2321,2347,2563,2607,2679,2703,2861,2869,2909,

%U 2959,3033,3067,3177,3333,3403,3437,3461,3471,3513,3601,3647,3769,3821,3833

%N Concatenation of n in base 2 up to base 10 is prime, all numbers are interpreted as decimals.

%H Harvey P. Dale, <a href="/A054256/b054256.txt">Table of n, a(n) for n = 0..1000</a>

%e a(1)=7 -> 111{2}=21{3}=13{4}=12{5}=11{6}=10{7}=7{8}=7{9}=7{10} -> 1112113121110777 is a prime.

%t Select[Range[4000],PrimeQ[FromDigits[Flatten[Table[IntegerDigits[#,n],{n,2,10}]]]]&] (* _Harvey P. Dale_, Aug 20 2017 *)

%Y Cf. A054257, A054258.

%K nonn,base

%O 0,1

%A _Patrick De Geest_, Feb 15 2000

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Last modified August 4 08:25 EDT 2020. Contains 336201 sequences. (Running on oeis4.)