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Primes prime(k) such that prime(k) + 2*prime(k+1) and prime(k) + 2*prime(k+1) + 4*prime(k+2) are prime.
2

%I #14 Aug 20 2020 13:40:35

%S 3,43,59,127,599,673,937,1451,1619,1847,2089,2311,2953,3343,3613,3677,

%T 4817,4909,4973,5519,5639,5857,6359,6389,7043,7069,7537,8867,9157,

%U 9341,10039,11069,12301,12907,13327,13729,14293,14549,15619,15739,15877,17077,17351,17977,18253,19211,19387,19469

%N Primes prime(k) such that prime(k) + 2*prime(k+1) and prime(k) + 2*prime(k+1) + 4*prime(k+2) are prime.

%H Robert Israel, <a href="/A337213/b337213.txt">Table of n, a(n) for n = 1..10000</a>

%e a(3)=59 is in the sequence because 59, 61, 67 are consecutive primes and 59+2*61=181 and 59+2*61+4*67=449 are prime.

%p N:= 2000: # to get terms in the first N primes

%p P:= [seq(ithprime(i),i=1..N+2)]:

%p P[select(i -> isprime(P[i]+2*P[i+1]) and isprime(P[i]+2*P[i+1]+4*P[i+2]), [$1..N])];

%Y Cf. A175914, A337214.

%K nonn

%O 1,1

%A _J. M. Bergot_ and _Robert Israel_, Aug 19 2020