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%I #16 Sep 14 2015 14:59:09
%S 2,19,181,1801,17989,179849,1798487,17984833,179848309,1798483067,
%T 17984830667,179848306667,1798483066669,17984830666651,
%U 179848306666507,1798483066665031,17984830666650269,179848306666502647
%N a(1) = 2; for n > 1, a(n) is largest prime < 10*a(n-1).
%H Charles R Greathouse IV, <a href="/A124262/b124262.txt">Table of n, a(n) for n = 1..1000</a>, extending and correcting a b-file from Artur Jasinski
%t NestList[NextPrime[10 #, -1]&, 2, 20] (* _Vincenzo Librandi_, Jun 28 2014 *)
%o (PARI) step(k)=precprime(10*k)
%o t=1/5; vector(10,n,t=step(t)) \\ _Charles R Greathouse IV_, Sep 14 2015
%Y Cf. A006902, A040016, A120031-A120040, A126041.
%K nonn
%O 1,1
%A _Artur Jasinski_, Dec 16 2006