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A285692 a(1) = 2; a(n + 1) = smallest prime > a(n) such that a(n + 1) - a(n) is the product of 7 primes.

%I A285692 #14 Dec 29 2022 09:49:39
%S A285692 2,9479,9767,10247,10567,11047,11239,11527,11719,12007,12487,12919,
%T A285692 13367,13687,13879,14071,14503,14951,15271,15559,15991,16183,16631,
%U A285692 16759,17047,17239,17431,17623,17911,18199,18679,19687,20359,20551,20743,21031,21319,21751,21943
%N A285692 a(1) = 2; a(n + 1) = smallest prime > a(n) such that a(n + 1) - a(n) is the product of 7 primes.
%C A285692 First differences: 9477, 288, 480, 320, 480, 192, 288, 192, 288, 480, 432, 448, 320, 192, 192, 432, 448, 320, 288, 432,...
%H A285692 Robert Israel, <a href="/A285692/b285692.txt">Table of n, a(n) for n = 1..10000</a>
%p A285692 A:= Vector(100): A[1]:= 2:
%p A285692 for n from 2 to 100 do
%p A285692   p:= A[n-1];
%p A285692   do
%p A285692     p:= nextprime(p);
%p A285692   until numtheory:-bigomega(p-A[n-1]) = 7;
%p A285692   A[n]:= p;
%p A285692 od:
%p A285692 convert(A,list); # _Robert Israel_, Dec 28 2022
%t A285692 NestList[Module[{p = NextPrime@ #}, While[PrimeOmega[p - #] != 7, p = NextPrime@ p]; p] &, 2, 38] (* _Michael De Vlieger_, Apr 25 2017 *)
%Y A285692 Cf. A255609, A285688, A285689, A285690, A285691.
%K A285692 nonn
%O A285692 1,1
%A A285692 _Zak Seidov_, Apr 25 2017