A247515 - OEIS

%I #12 Oct 24 2023 05:17:19

%S 2,4,6,9,11,14,15,17,18,21,22,25,30,33,34,37,38,39,43,44,47,48,53,54,

%T 59,60,61,63,64,65,66,69,70,71,72,76,77,78,82,83,84,85,90,91,92,97,98,

%U 99,102,103,104,105,110,111,112,113,114,119,120,121,122,127

%N Numbers k such that 2*floor(sqrt(prime(k))) < floor(2*sqrt(prime(k))).

%C A117767(a(n)) < A247485(a(n)); complement of A247514.

%H Reinhard Zumkeller, <a href="/A247515/b247515.txt">Table of n, a(n) for n = 1..10000</a>

%t A247515Q[k_]:=With[{r=Sqrt[Prime[k]]},2Floor[r]<Floor[2r]];

%t Select[Range[200],A247515Q] (* _Paolo Xausa_, Oct 23 2023 *)

%o (Haskell)

%o a247515 n = a247515_list !! (n-1)

%o a247515_list = filter (\x -> a117767 x < a247485 x) [1..]

%Y Cf. A117767, A247485, A000196, A000040, A000006, A247514.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Sep 20 2014