OFFSET
1,1
COMMENTS
Subsequence of A033560. The triples have the form (p,p+d,p+2d). The current sequence (d=24) continues A023241 (d=6), A185022 (d=12) and A156109 (d=18). The frequencies of such triples and the triple (p, p+3±1, p+6) in A007529 do not differ very much (see table in the link "comparison of triples"). For creating the b-file I used a file of prime differences, divided by 2 (extension of A028334). For filling the table I analyzed primes up to 10^9.
Annotation: The algorithm using a file of primes or prime differences is not difficult but not as easy as using a function like isprime(n). On the other hand, such a function needs computing time which is not negligible for large numbers.
LINKS
Gerhard Kirchner, Table of n, a(n) for n = 1..10000
Gerhard Kirchner, Comparison of triples
EXAMPLE
First term: 5, 5 + 24 = 29 and 5 + 48 = 53 are all primes.
MATHEMATICA
Select[Prime@Range@500, PrimeQ[# + 24] && PrimeQ[# + 48] &] (* Robert G. Wilson v, Dec 18 2016 *)
PROG
(PARI) is(n) = for(k=0, 2, if(!ispseudoprime(n+24*k), return(0))); 1 \\ Felix Fröhlich, Dec 26 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
Gerhard Kirchner, Dec 18 2016
STATUS
approved