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Numbers k such that k235711 is prime.
1

%I #14 Jan 17 2023 11:57:22

%S 1,3,9,12,15,27,34,37,43,45,46,55,61,66,72,75,82,93,94,106,117,130,

%T 132,138,139,142,144,145,157,163,165,169,181,198,199,205,214,222,237,

%U 256,258,274,276,289,297,300,309,310,319,324,331,333,337,339,355,361,367,384,387,390,397

%N Numbers k such that k235711 is prime.

%H Harvey P. Dale, <a href="/A103531/b103531.txt">Table of n, a(n) for n = 1..1000</a>

%e k=1 is in the sequence because k235711 = 1235711 is prime.

%e k=37 is in the sequence because k235711 = 37235711 is prime.

%e k=72 is in the sequence because k235711 = 72235711 is prime.

%t Select[Range[400],PrimeQ[10^6 #+235711]&] (* _Harvey P. Dale_, Jan 17 2023 *)

%o (Magma) [ n: n in [1..700] | IsPrime(Seqint([1, 1, 7, 5, 3, 2] cat Intseq(n))) ]; // _Vincenzo Librandi_, Feb 03 2011

%K base,nonn

%O 1,2

%A _Parthasarathy Nambi_, Mar 21 2005