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%I #28 Sep 08 2022 08:45:32
%S 1,2,7,18,33,206,468,1061,6831,40377
%N n such that floor(sqrt(10^(2*n-1))) is (probably) prime.
%C Number of digits of sqrt(10)-primes (A136582).
%C The n such that A017934(2*n-1) is (probably) prime.
%t rd = RealDigits[Sqrt[10], 10, 10^5][[1]]; Do[ If[ PrimeQ@ FromDigits@ Take[rd, n], Print@n], {n, 10^5}] (* _Robert G. Wilson v_, Jan 20 2008 *)
%o (Magma) for n in [1..10^6] do if IsPrime(Isqrt(10^(2*n-1))) then printf "%o, ", n; end if; end for; // _Jason Kimberley_, Sep 03 2011
%Y Cf. A010467, A017934, A017934, A131581, A132153, A136582, A175733, A175734.
%K nonn,base,more
%O 1,2
%A _Lekraj Beedassy_, Jan 09 2008
%E a(6) - a(8) from _Robert G. Wilson v_, Jan 20 2008
%E Probable terms a(9) and a(10) from _Jason Kimberley_, Aug 19 and Sep 03 2011
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