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Prime numbers ending in the prime number 11.
7

%I #16 Sep 08 2022 08:45:48

%S 11,211,311,811,911,1511,1811,2011,2111,2311,2411,2711,3011,3511,3911,

%T 4111,4211,5011,5711,6011,6211,6311,6911,7211,7411,8011,8111,8311,

%U 9011,9311,9511,9811,10111,10211,10711,11311,11411,12011,12211,12511,12611

%N Prime numbers ending in the prime number 11.

%C Also primes of the form 100*n+11. - _Vincenzo Librandi_, Jul 07 2014

%H Vincenzo Librandi, <a href="/A167442/b167442.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Prime[Range[5, 6000]], Take[IntegerDigits[#], -2]=={1, 1} &] (* _Vincenzo Librandi_, Jul 07 2014 *)

%t Select[Range[11,20011,100],PrimeQ] (* _Harvey P. Dale_, Nov 09 2014 *)

%o (Magma) [n: n in PrimesUpTo(15000) | n mod 100 eq 11]; // _Vincenzo Librandi_, Jul 07 2014

%o (PARI) select(x->(x % 100)==11, primes(2000)) \\ _Michel Marcus_, Jul 07 2014

%Y Cf. A101471.

%Y Cf. similar sequences listed in A244763.

%K base,nonn

%O 1,1

%A _Mark A. Thomas_, Nov 03 2009