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%I #18 Oct 24 2023 10:09:27
%S 1,3,5,7,8,10,12,13,16,19,20,23,24,26,27,28,29,31,32,35,36,40,41,42,
%T 45,46,49,50,51,52,55,56,57,58,62,67,68,73,74,75,79,80,81,86,87,88,89,
%U 93,94,95,96,100,101,106,107,108,109,115,116,117,118,123,124
%N Numbers k such that 2*floor(sqrt(prime(k))) = floor(2*sqrt(prime(k))).
%C A117767(a(n)) = A247485(a(n)); complement of A247515.
%H Reinhard Zumkeller, <a href="/A247514/b247514.txt">Table of n, a(n) for n = 1..10000</a>
%t A247514Q[k_]:=With[{r=Sqrt[Prime[k]]},2Floor[r]==Floor[2r]];
%t Select[Range[200],A247514Q] (* _Paolo Xausa_, Oct 23 2023 *)
%o (Haskell)
%o a247514 n = a247514_list !! (n-1)
%o a247514_list = filter (\x -> a117767 x == a247485 x) [1..]
%o (PARI) isok(k) = my(p=prime(k)); 2*sqrtint(p) == sqrtint(4*p); \\ _Michel Marcus_, Apr 29 2023
%Y Cf. A117767, A247485, A000196, A000040, A000006, A247515.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Sep 20 2014
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