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A027867 Primes of the form n^2 + (n+1)^2 + (n+2)^2 + (n+3)^2 + (n+4)^2 + (n+5)^2. 5

%I

%S 139,199,271,811,1279,1459,2539,2791,3331,3919,4231,7159,8011,9859,

%T 15319,17191,17839,20551,24979,25759,41851,42859,48079,58231,59419,

%U 65539,68071,74611,88591,102199,125299,132331,143239,154579,156511,166351,170371,172399,243631,276079,281251,289099,294391

%N Primes of the form n^2 + (n+1)^2 + (n+2)^2 + (n+3)^2 + (n+4)^2 + (n+5)^2.

%C Primes of form 55 + 30n + 6n^2. - _Zak Seidov_, May 20 2014

%C All terms == 1 or 19 (mod 30). - _Robert Israel_, Jul 18 2017

%H Robert Israel, <a href="/A027867/b027867.txt">Table of n, a(n) for n = 1..10000</a>

%H P. De Geest, <a href="http://www.worldofnumbers.com/index.html">World!Of Numbers</a>

%F a(n) = 55 + 30*m + 6*m^2 where m = A027866(n). - _Zak Seidov_, May 20 2014

%p select(isprime, [seq(6*t^2-30*t+55, t=6..1000)]); # _Robert Israel_, Jul 18 2017

%t lst={};Do[a=n^2+(n+1)^2+(n+2)^2+(n+3)^2+(n+4)^2+(n+5)^2;If[PrimeQ[a],AppendTo[lst,a]],{n,8!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Jun 02 2009 *)

%t Select[Table[Total[(n+Range[0,5])^2],{n,200}],PrimeQ] (* _Harvey P. Dale_, Jul 18 2011 *)

%Y Cf. A027866.

%K nonn

%O 1,1

%A _Patrick De Geest_

%E More terms from _Robert Israel_, Jul 18 2017

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Last modified October 15 15:03 EDT 2019. Contains 328030 sequences. (Running on oeis4.)