A368691 Primes p such that p + 4 * q is prime, where q is the next prime after p.
3, 23, 31, 73, 83, 157, 167, 211, 251, 353, 373, 443, 467, 503, 509, 523, 541, 571, 647, 727, 751, 941, 947, 977, 1033, 1069, 1123, 1201, 1259, 1361, 1381, 1493, 1511, 1531, 1553, 1613, 1759, 1811, 2011, 2207, 2333, 2351, 2383, 2399, 2417, 2543, 2777, 2927, 3061, 3067, 3083, 3301, 3331, 3511
Offset: 1
Keywords
Examples
a(3) = 31 is a term because 31 is prime, the next prime is 37, and 31 + 4 * 37 = 179 is prime.
Links
- Robert Israel, Table of n, a(n) for n = 1..10000
Crossrefs
Cf. A175914.
Programs
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Maple
filter:= proc(p) local q; if not isprime(p) then return false fi; q:= nextprime(p); isprime(p+4*q) end proc: select(filter, [seq(i,i=3..10000,2)]);
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Mathematica
f[p_] := Module[{q}, If[!PrimeQ[p], Return[False]]; q = NextPrime[p]; PrimeQ[p + 4*q]];Select[Range[3,3511, 2],f] (* James C. McMahon, Jan 03 2024 *)