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A156204 First primes of an arithmetic progression of six primes with common difference 30. 8
7, 107, 359, 541, 2221, 6673, 7457, 10103, 25643, 26861, 27337, 35051, 56149, 61553, 65557, 73523, 84317, 110819, 115733, 131581, 135151, 137447, 179321, 228587, 243553, 252163, 279421, 281717, 310711, 320119, 337367, 345487, 347167, 357079 (list; graph; refs; listen; history; text; internal format)
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

Cf. A155760, A227281.

Sequence in context: A141932 A002687 A166547 * A231519 A197447 A202780

Adjacent sequences:  A156201 A156202 A156203 * A156205 A156206 A156207

KEYWORD

nonn

AUTHOR

Ki Punches, Feb 05 2009

EXTENSIONS

Corrected and extended by R. J. Mathar and Ray Chandler, Feb 08 2009

STATUS

approved

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Last modified March 30 12:09 EDT 2017. Contains 284302 sequences.