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 A018074 #21 Jul 08 2025 06:23:09 %S A018074 1,2,4,6,10,18,32,57,100,178,317,563,1000,1779,3163,5624,10000,17783, %T A018074 31623,56235,100000,177828,316228,562342,1000000,1778280,3162278, %U A018074 5623414,10000000,17782795,31622777,56234133,100000000,177827942,316227767,562341326,1000000000 %N A018074 Powers of fourth root of 10 rounded up. %t A018074 Ceiling[(Power[10, (4 )^-1])^Range[0,50]] (* _Harvey P. Dale_, Mar 18 2011 *) %o A018074 (PARI) a(n) = sqrtnint(10^n-1, 4) + 1; \\ _Michel Marcus_, Jun 26 2024 %Y A018074 Cf. A011007, A017936 (bisection), A308467. %K A018074 nonn %O A018074 0,2 %A A018074 _N. J. A. Sloane_ %E A018074 More terms from _Michel Marcus_, Aug 21 2019