A253976 Primes p such that (p^2 + 5)/6, (p^4 + 5)/6, (p^6 + 5)/6 and (p^8 + 5)/6 are prime.
67103, 7524593, 9938069, 10125793, 13042637, 55741139, 55792241, 58429099, 77618323, 92713879, 94554613, 96242761, 103774049, 119753549, 141725501, 142915193, 164899799, 165227399, 173202247, 174728233, 178411771, 184279409, 184356703, 186622003, 195863347, 200406977, 239488649
Offset: 1
Keywords
Links
- Zak Seidov, Table of n, a(n) for n = 1..503 (all terms up to 10^10)
Programs
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Mathematica
Select[Prime[Range[132*10^5]],AllTrue[(#^Range[2,8,2]+5)/6,PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, May 11 2018 *)
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PARI
forprime(p=1,10^7,k=0;for(i=1,4,P=(p^(2*i)+5)/6;if(P\1==P,if(ispseudoprime(P),k++);if(!ispseudoprime(P),k=0;break));if(P\1!=P,k=0;break));if(k,print1(p,", "))) \\ Derek Orr, Jan 21 2015