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A155140 Primes p such that both p-+4 are not squarefree. 5

%I #11 Jul 06 2016 02:32:13

%S 293,347,571,829,1021,1229,1327,1373,1471,1621,2111,2129,2371,2531,

%T 2579,2879,2887,3181,3271,3929,4621,4801,4909,5279,5333,5521,5639,

%U 5683,5827,6133,6421,6521,6709,6863,6871,7079,7321,7529,7591,8179,8221,8429,8963

%N Primes p such that both p-+4 are not squarefree.

%H John Cerkan, <a href="/A155140/b155140.txt">Table of n, a(n) for n = 1..10000</a>

%t <<NumberTheory`NumberTheoryFunctions` lst={};Do[p=Prime[n];If[ !SquareFreeQ[p-4]&&!SquareFreeQ[p+4],AppendTo[lst,p]],{n,7!}];lst

%o (PARI) lista(nn) = forprime(p=2, nn, if (! issquarefree(p-4) && ! issquarefree(p+4), print1(p, ", "))); \\ _Michel Marcus_, Jul 05 2016

%Y Cf. A153213, A049282, A155139, A155141, A155142.

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Jan 21 2009

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Last modified June 20 11:12 EDT 2024. Contains 373527 sequences. (Running on oeis4.)