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Largest square <= n-th prime.
14

%I #28 Dec 28 2024 11:12:40

%S 1,1,4,4,9,9,16,16,16,25,25,36,36,36,36,49,49,49,64,64,64,64,81,81,81,

%T 100,100,100,100,100,121,121,121,121,144,144,144,144,144,169,169,169,

%U 169,169,196,196,196,196,225,225,225,225,225,225,256,256,256,256,256

%N Largest square <= n-th prime.

%C For n > 2: a(n) = A257053(n,0). - _Reinhard Zumkeller_, Apr 15 2015

%H Harry J. Smith, <a href="/A065730/b065730.txt">Table of n, a(n) for n=1..1000</a>

%F a(n) = A048760(A000040(n)).

%t Table[Floor[Sqrt@ Prime@ n]^2, {n, 60}] (* _Michael De Vlieger_, Jul 03 2016 *)

%o (PARI) a(n) = { sqrtint(prime(n))^2 } \\ _Harry J. Smith_, Oct 28 2009

%o (Haskell)

%o a065730 = a048760 . a000040 -- _Reinhard Zumkeller_, Apr 15 2015

%o (Magma) [Floor(Sqrt(NthPrime(n)))^2: n in [1..70]]; // _Vincenzo Librandi_, Jan 05 2018

%Y Cf. A048760, A000040, A065731-A065741.

%Y Cf. A257053.

%K easy,nonn

%O 1,3

%A _Labos Elemer_, Nov 15 2001