A356593 - OEIS

%I #11 Aug 19 2022 10:09:02

%S 1,2,3,3,3,4,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,

%T 5,5,5,5,5,5,5,5,5,5,5,5,5,5,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,

%U 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6

%N Smallest k such that primorial(k) > n^2.

%t a[n_] := Module[{k = 1, prod = p = 2}, While[prod < n^2, p = NextPrime[p]; prod *= p; k++]; k]; Array[a, 100] (* _Amiram Eldar_, Aug 15 2022 *)

%o (Python)

%o from sympy import primorial

%o def a(n):

%o     k = 1

%o     while True:

%o         if primorial(k) > n**2:

%o             return(k)

%o         k += 1

%o for n in range(1, 90):

%o     print(f'{a(n)}, ', end='')

%Y Cf. A337769, A002110, A000290.

%K nonn

%O 1,2

%A _Christoph B. Kassir_, Aug 14 2022