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 A379568 #28 Dec 30 2024 04:27:48
%S A379568 0,2,1,1,3,4,5,9,15,25,37,66,107,171,293,490,810,1362,2302,3889,6552,
%T A379568 11149,18950,32255,55053,94096,161036,275896,473709,813669,1399593,
%U A379568 2409905,4154437,7166774,12375776,21389092,36994679,64034719,110918422,192257157,333449674,578697626
%N A379568 Number of n-digit numbers that have exactly 5 divisors.
%C A379568 A number has exactly 5 divisors if and only if it is the fourth power of a prime. - _David Radcliffe_, Dec 29 2024
%H A379568 David Radcliffe, <a href="/A379568/b379568.txt">Table of n, a(n) for n = 1..57</a>
%F A379568 a(n) = PrimePi(10^(n/4)) - PrimePi(10^((n-1)/4)). - _David Radcliffe_, Dec 29 2024
%t A379568 Table[PrimePi[10^(n/4)]-PrimePi[10^((n-1)/4)],{n,50}] (* _Vincenzo Librandi_, Dec 30 2024 *)
%o A379568 (Python)
%o A379568 from sympy import primepi
%o A379568 def a379568(n): return primepi(10**(n/4)) - primepi(10**((n-1)/4)) # _David Radcliffe_, Dec 29 2024
%Y A379568 Column k=5 of A284398.
%Y A379568 Cf. A006880, A379566.
%K A379568 nonn,base
%O A379568 1,2
%A A379568 _Seiichi Manyama_, Dec 26 2024
%E A379568 a(36)-a(42) from _David Radcliffe_, Dec 29 2024