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A101792 Primes of the form 8*k-1 such that 4*k-1 and 16*k-1 are also primes.

%I A101792 #15 May 13 2024 02:15:02
%S A101792 23,359,719,1439,2039,2063,2903,3023,3623,3863,4919,5399,5639,6983,
%T A101792 7079,7823,10799,12263,14159,14303,21383,22343,22943,24239,25799,
%U A101792 25919,33623,34319,36383,38639,39983,40823,42023,42359,44543,46199,47639,48479,49103,54959
%N A101792 Primes of the form 8*k-1 such that 4*k-1 and 16*k-1 are also primes.
%H A101792 Amiram Eldar, <a href="/A101792/b101792.txt">Table of n, a(n) for n = 1..10000</a>
%F A101792 a(n) = 8*A101790(n) - 1 = 2*A101791(n) + 1. - _Amiram Eldar_, May 13 2024
%e A101792 4*3 - 1 = 11, 8*3 - 1 = 23 and 16*3 - 1 = 47 are primes, so 23 is a term.
%t A101792 8 * Select[Range[10^4], And @@ PrimeQ[2^Range[2, 4]*# - 1] &] - 1 (* _Amiram Eldar_, May 13 2024 *)
%o A101792 (PARI) for(k=1,7000,if(isprime(8*k-1)&&isprime(4*k-1)&&isprime(16*k-1),print1(8*k-1,", "))) \\ _Hugo Pfoertner_, Sep 07 2021
%Y A101792 Cf. A002515, A101790, A101791, A101793.
%Y A101792 Subsequence of A007522.
%Y A101792 Subsequences: A101796, A101996.
%K A101792 easy,nonn
%O A101792 1,1
%A A101792 Douglas Stones (dssto1(AT)student.monash.edu.au), Dec 16 2004