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%I #14 Jul 27 2024 15:37:08
%S 1,5,14,406,1118,4934
%N Numbers n such that the largest prime < 10^n is a twin prime member.
%C A003618(a(n)) is in A001097 (Twin primes).
%e For n=1, 10^1 = 10. 7, the greatest prime < 10, is a member of the twin prime pair 5,7.
%t Select[Range[410],PrimeQ[NextPrime[10^#,-1]-2]&] (* The program generates the first four terms of the sequence. *) (* _Harvey P. Dale_, Jul 26 2024 *)
%o (PARI) g(n)=for(x=1,n,y=precprime(10^x);if(ispseudoprime(y-2),print1(x",")))
%K hard,more,nonn
%O 1,2
%A _Cino Hilliard_, Apr 28 2007
%E Edited by _Ray Chandler_, May 12 2007
%E a(5), a(6) from _Donovan Johnson_, Feb 21 2008
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