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A033450 List of sets of four consecutive primes in arithmetic progression with common difference 18.

%I A033450 #29 Dec 04 2023 01:51:10
%S A033450 74453,74471,74489,74507,76543,76561,76579,76597,132893,132911,132929,
%T A033450 132947,182243,182261,182279,182297,202823,202841,202859,202877,
%U A033450 297403,297421,297439,297457,358793,358811,358829,358847,485923,485941,485959,485977
%N A033450 List of sets of four consecutive primes in arithmetic progression with common difference 18.
%C A033450 This is a 4-column table read by rows.
%H A033450 Robert Price, <a href="/A033450/b033450.txt">Table of n, a(n) for n = 1..6032</a>
%H A033450 <a href="/index/Pri#primes_AP">Index entries for sequences related to primes in arithmetic progressions</a>
%p A033450 a:=[];
%p A033450 for n from 1 to 50000 do
%p A033450   p1:=ithprime(n);
%p A033450   p2:=nextprime(p1);
%p A033450 if (p2-p1)=18 then
%p A033450   p3:=nextprime(p2);
%p A033450      if p3-p2=18 then
%p A033450         p4:=nextprime(p3);
%p A033450          if p4-p3 = 18 then a:=[op(a),p1,p2,p3,p4]; fi;
%p A033450      fi;
%p A033450 fi;
%p A033450 od:
%p A033450 a; # _N. J. A. Sloane_, Nov 23 2017
%t A033450 Select[Partition[Prime[Range[41000]],4,1],Union[Differences[#]]=={18}&]// Flatten (* _Harvey P. Dale_, Nov 24 2017 *)
%Y A033450 For the initial primes from each set of four, see A033448.
%K A033450 nonn,tabf
%O A033450 1,1
%A A033450 _Jeff Burch_
%E A033450 Confirmed (and last set of four completed) by _N. J. A. Sloane_, Nov 23 2017