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A248085
Initial prime of 4 primes in arithmetic progression with difference 12.
2
5, 7, 17, 47, 127, 227, 257, 397, 467, 607, 997, 1447, 1487, 1697, 1877, 2647, 3307, 3547, 3907, 4217, 4987, 5407, 6287, 6947, 7297, 7537, 7817, 10067, 10627, 11047, 11777, 12227, 12577, 13147, 14747, 15137, 15737, 15877, 17827, 19727, 19937, 20707, 21577, 22027, 22247, 23017, 24097, 26017
OFFSET
1,1
COMMENTS
Or, primes p such that p + 12, p + 24 and p + 36 are also primes.
Primes are not necessarily consecutive ones. A033447 is subsequence: a(92) = 111497 = A033447(1), a(144) = 258527 = A033447(2), etc.
The only case with p + 48 prime is p = 5, in all other cases p + 48 is divisible by 5.
All terms >5 are congruent to 7 (mod 10). - Zak Seidov, Jun 12 2018
LINKS
MAPLE
A248085:=n->`if`(isprime(n) and isprime(n+12) and isprime(n+24) and isprime(n+36), n, NULL): seq(A248085(n), n=1..10^5); # Wesley Ivan Hurt, Oct 01 2014
MATHEMATICA
Select[Prime[Range[1000]], PrimeQ[# + 12] && PrimeQ[# + 24] && PrimeQ[# + 36] &] (* Alonso del Arte, Oct 01 2014 *)
Select[Prime[Range[3000]], AllTrue[#+{12, 24, 36}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Feb 08 2016 *)
PROG
(PARI) forprime(p=5, 10^5, isprime(p+12)&&isprime(p+24)&&isprime(p+36)&&print1(p", "))
CROSSREFS
Cf. A033447.
Sequence in context: A106955 A030785 A019404 * A079604 A101580 A190663
KEYWORD
nonn
AUTHOR
Zak Seidov, Oct 01 2014
STATUS
approved