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A280895 For any n>=0, least prime k = p^d-2*n, where p is a prime and d is its number of digits.

%I A280895 #8 Jan 11 2017 03:19:05
%S A280895 2,3,3,163,113,1030291,109,107,2571337,103,101,2248069,97,263,1442869,
%T A280895 139,89,1225009,2685583,83,2571313,79,317,2571307,73,71,1224991,67,
%U A280895 113,3307891,61,59,104633567005988371387,103,53,1224973,97,47,1224967,43,41,1030219,37
%N A280895 For any n>=0, least prime k = p^d-2*n, where p is a prime and d is its number of digits.
%H A280895 Paolo P. Lava, <a href="/A280895/b280895.txt">Table of n, a(n) for n = 0..1000</a>
%e A280895 a(5) = 1030291 because 1030291 is the least prime such that 101^3 - 2*5 = 1030301 - 10 = 1030291.
%p A280895 P:=proc(q) local a,b,k,n; for n from 0 to q do for k from 1 to q do a:=ithprime(k);
%p A280895 b:=a^(ilog10(a)+1)-2*n; if isprime(b) then lprint(n,b); break; fi; od; od; end: P(1000);
%Y A280895 Cf. A055642, A280427
%K A280895 nonn,base
%O A280895 0,1
%A A280895 _Paolo P. Lava_, Jan 10 2017