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Largest square <= product of first n primes.
1

%I #11 Jan 13 2024 15:21:05

%S 1,4,25,196,2304,29929,509796,9696996,223084096,6469628356,

%T 200559769921,7420737154609,304250260158441,13082761295250201,

%U 614889781233144561,32589158470911505225,1922760350143213168900

%N Largest square <= product of first n primes.

%H Harry J. Smith, <a href="/A065735/b065735.txt">Table of n, a(n) for n = 1..100</a>

%F a(n) = A048760(A002110(n)).

%t Floor[Sqrt[#]]^2&/@FoldList[Times,Prime[Range[20]]] (* _Harvey P. Dale_, Jan 13 2024 *)

%o (PARI) { m=1; for (n=1, 100, m*=prime(n); a=sqrtint(m)^2; write("b065735.txt", n, " ", a) ) } \\ _Harry J. Smith_, Oct 28 2009

%Y Cf. A048760, A002110, A065730-A065741.

%K easy,nonn

%O 1,2

%A _Labos Elemer_, Nov 15 2001