The On-Line Encyclopedia of Integer Sequences (OEIS)

A033447 revision #45

A033447

Initial prime in set of 4 consecutive primes with common difference 12.

111497, 258527, 286777, 318407, 332767, 341827, 358447, 439787, 473887, 480737, 495377, 634187, 647417, 658367, 663857, 703837, 732497, 816317, 819787, 827767, 843067, 862307, 937777, 970457, 970537, 1001267, 1012147, 1032727, 1052707, 1055827, 1104307, 1117877, 1164817, 1165837

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OFFSET

1,1

COMMENTS

From Zak Seidov, Sep 30 2014: (Start)

All terms are == {7, 17} mod 30. There is no set of 5 consecutive primes in arithmetic progression with common difference 12 (because a(n)+48 is always divisible by 5).

Minimal first difference a(n+1)-a(n) = 40, and this occurs first at a(709) = 26930767, a(11357) = 655389367 and a(23339) = 1510368877; all a(n) are == 7 mod 30. (End)

LINKS

Zak Seidov, Table of n, a(n) for n = 1..1000

Index entries for sequences related to primes in arithmetic progressions

MATHEMATICA

A033447 = Reap[For[p = 2, p < 1100000, p = NextPrime[p], p2 = NextPrime[p]; If[p2 - p == 12, p3 = NextPrime[p2]; If[p3 - p2 == 12, p4 = NextPrime[p3]; If[p4 - p3 == 12, Sow[p]]]]]][[2, 1]] (* Jean-François Alcover, Jun 28 2012 *)

Transpose[Select[Partition[Prime[Range[160000]], 4, 1], Union[ Differences[#]] =={12}&]][[1]] (* Harvey P. Dale, Jun 17 2014 *)

PROG

(PARI) A033447(n, p=2, show_all=1, g=12, c, o)={forprime(q=p+1, , if(p+g!=p=q, next, q!=o+2*g, c=2, c++>3, show_all&& print1(o-g", "); n--||break); o=q-g); o-g} \\ Can be used as next(p)=A033447(1, p+1) to get the next term, e.g.:

p=0; A033447_vec=vector(30, i, p=A033447(1, p+1)) \\ M. F. Hasler, Oct 26 2018

CROSSREFS

Analogous sequences [with common difference in square brackets]: A033451 [6], this sequence [12], A033448 [18], A052242 [24], A052243 [30], A058252 [36].

Subsequence of A052188 and of A248085. - Zak Seidov, Jun 27 2015

Sequence in context: A296370 A206509 A033446 * A203667 A210059 A236892

Adjacent sequences: A033444 A033445 A033446 * A033448 A033449 A033450

KEYWORD

nonn

AUTHOR

Jeff Burch

EXTENSIONS

More terms from Labos Elemer, Jan 31 2000

Definition clarified by Harvey P. Dale, Jun 17 2014

STATUS

editing