This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A380331 #15 Jan 23 2025 15:34:42
%S A380331 0,0,6,22,54,114,210,357,564,847,1229,1715,2334,3107,4052,5191,6542,
%T A380331 8152,10022,12187,14683,17531,20768,24421,28546,33118,38236,43934,
%U A380331 50203,57097,64683,72992,82025,91932,102588,114204,126726,140235,154787,170426,187134
%N A380331 a(n) = number of primes < n^4.
%H A380331 Charles R Greathouse IV, <a href="/A380331/b380331.txt">Table of n, a(n) for n = 0..10000</a>
%F A380331 a(n) = A000720(A000583(n)). - _Pontus von Brömssen_, Jan 21 2025
%F A380331 a(n) ~ (1/4)*n^4/log n. - _Charles R Greathouse IV_, Jan 23 2025
%e A380331 a(2) = 6 because there are 6 primes < 16.
%t A380331 Table[PrimePi[n^4], {n, 0, 60}]
%o A380331 (PARI) a(n)=primepi(n^4) \\ _Charles R Greathouse IV_, Jan 21 2025
%o A380331 (Python)
%o A380331 from sympy import primepi
%o A380331 def A380331(n): return primepi(n**4) # _Chai Wah Wu_, Jan 23 2025
%Y A380331 Subsequence of A038107, and hence of A000720.
%Y A380331 Cf. A000040, A000583.
%K A380331 nonn
%O A380331 0,3
%A A380331 _Clark Kimberling_, Jan 21 2025