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A285690 a(1) = 2; a(n + 1) = smallest prime > a(n) such that a(n + 1) - a(n) is the product of five primes.

%I A285690 #12 Nov 05 2019 00:57:23
%S A285690 2,569,601,673,853,1021,1069,1117,1229,1277,1439,1471,1543,1663,1783,
%T A285690 1831,1879,1951,1999,2111,2143,2251,2371,2539,2647,2719,2767,2879,
%U A285690 2927,2999,3079,3187,3259,3307,3469,3517,3637,3709,3821,3853,4021,4093,4201
%N A285690 a(1) = 2; a(n + 1) = smallest prime > a(n) such that a(n + 1) - a(n) is the product of five primes.
%C A285690 First differences: 567, 32, 72, 180, 168, 48, 48, 112, 48, 162, 32, 72, 120, 120, 48, 48, 72, 48, 112, 32, ...
%H A285690 Robert Israel, <a href="/A285690/b285690.txt">Table of n, a(n) for n = 1..10000</a>
%p A285690 A[1]:= 2:
%p A285690 for n from 2 to 100 do
%p A285690   p:= A[n-1];
%p A285690   do
%p A285690     p:= nextprime(p);
%p A285690     if numtheory:-bigomega(p-A[n-1])=5 then A[n]:= p; break fi
%p A285690 od od:
%p A285690 seq(A[i],i=1..100); # _Robert Israel_, Nov 04 2019
%t A285690 NestList[Module[{p = NextPrime@ #}, While[PrimeOmega[p - #] != 5, p = NextPrime@ p]; p] &, 2, 40] (* _Michael De Vlieger_, Apr 25 2017 *)
%Y A285690 Cf. A255609, A285688, A285689.
%K A285690 nonn
%O A285690 1,1
%A A285690 _Zak Seidov_, Apr 24 2017