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A065730
Largest square <= n-th prime.
14
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, 100, 100, 100, 100, 100, 121, 121, 121, 121, 144, 144, 144, 144, 144, 169, 169, 169, 169, 169, 196, 196, 196, 196, 225, 225, 225, 225, 225, 225, 256, 256, 256, 256, 256
OFFSET
1,3
COMMENTS
For n > 2: a(n) = A257053(n,0). - Reinhard Zumkeller, Apr 15 2015
LINKS
FORMULA
a(n) = A048760(A000040(n)).
MATHEMATICA
Table[Floor[Sqrt@ Prime@ n]^2, {n, 60}] (* Michael De Vlieger, Jul 03 2016 *)
PROG
(PARI) a(n) = { sqrtint(prime(n))^2 } \\ Harry J. Smith, Oct 28 2009
(Haskell)
a065730 = a048760 . a000040 -- Reinhard Zumkeller, Apr 15 2015
(Magma) [Floor(Sqrt(NthPrime(n)))^2: n in [1..70]] // Vincenzo Librandi, Jan 05 2018
CROSSREFS
KEYWORD
easy,nonn,changed
AUTHOR
Labos Elemer, Nov 15 2001
STATUS
approved