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 A018033 #14 Feb 14 2025 17:10:33
%S A018033 1,2,7,20,54,147,400,1085,2947,8000,21715,58944,160000,434306,1178890,
%T A018033 3200000,8686136,23577801,64000000,173722727,471556031,1280000000,
%U A018033 3474454549,9431120636,25600000000,69489090984,188622412730,512000000000,1389781819696
%N A018033 Powers of cube root of 20 rounded down.
%H A018033 Vincenzo Librandi, <a href="/A018033/b018033.txt">Table of n, a(n) for n = 0..200</a>
%t A018033 Table[Floor[20^(n/3)], {n, 0, 40}] (* _Vincenzo Librandi_, Jan 06 2014 *)
%t A018033 Floor[CubeRoot[20]^Range[0,30]] (* _Harvey P. Dale_, Feb 14 2025 *)
%o A018033 (Magma) [Floor(20^(n/3)): n in [0..40]]; // _Vincenzo Librandi_, Jan 06 2014
%Y A018033 Cf. powers of cube root of k rounded down: A017979 (k=2), A017982 (k=3), A017985 (k=4), A017988 (k=5), A017991 (k=6), A017994 (k=7), A018000 (k=9), A018003 (k=10), A018006 (k=11), A018009 (k=12), A018012 (k=13), A018015 (k=14), A018018 (k=15), A018021 (k=16), A018024 (k=17), A018027 (k=18), A018030 (k=19), this sequence (k=20), A018036 (k=21), A018039 (k=22), A018042 (k=23), A018045 (k=24).
%K A018033 nonn
%O A018033 0,2
%A A018033 _N. J. A. Sloane_
%E A018033 More terms from _Vincenzo Librandi_, Jan 06 2014