OFFSET
1,1
COMMENTS
Subsequence of A155760. - R. J. Mathar, Feb 07 2009
After the first term, all terms are congruent to 9 (mod 14). Gaps of 14 occur at a(n) = 22037759, 400852853, ... - Zak Seidov, Aug 01 2013
Subsequence of A227281. - Zak Seidov, Aug 26 2014
Note that a(n)+6*30 is composite for all n: a(1)+180 is divisible by 11 and for n>1 a(n)+180 is divisible by 7. - Zak Seidov, Apr 11 2015
LINKS
Michael B. Porter, Table of n, a(n) for n = 1..10000
MAPLE
for n from 1 to 60000 do p := ithprime(n) ; if isprime(p+30) and isprime(p+60) and isprime(p+90) and isprime(p+120) and isprime(p+150) then printf("%d, ", p) ; fi; od: # R. J. Mathar, Feb 07 2009
MATHEMATICA
Select[Range[360000], PrimeQ[#] && PrimeQ[# + 30] && PrimeQ[# + 60] && PrimeQ[# + 90] && PrimeQ[# + 120] && PrimeQ[# + 150] &] (* Vincenzo Librandi, Apr 13 2015 *)
PROG
(PARI) is_A156204(n) = isprime(n) && isprime(n+30) && isprime(n+60) && isprime(n+90) && isprime(n+120) && isprime(n+150) \\ Michael B. Porter, Aug 01 2013
(Magma) [p: p in PrimesUpTo(360000)| IsPrime(p+30) and IsPrime(p+60) and IsPrime(p+90)and IsPrime(p+120)and IsPrime(p+150)]; // Vincenzo Librandi, Apr 13 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
Ki Punches, Feb 05 2009
EXTENSIONS
Corrected and extended by R. J. Mathar and Ray Chandler, Feb 08 2009
STATUS
approved