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 A018021 #11 Sep 08 2022 08:44:44
%S A018021 1,2,6,16,40,101,256,645,1625,4096,10321,26007,65536,165140,416127,
%T A018021 1048576,2642245,6658042,16777216,42275935,106528681,268435456,
%U A018021 676414963,1704458900,4294967296,10822639409,27271342415,68719476736,173162230554,436341478645
%N A018021 Powers of cube root of 16 rounded down.
%H A018021 Vincenzo Librandi, <a href="/A018021/b018021.txt">Table of n, a(n) for n = 0..200</a>
%t A018021 Table[Floor[16^(n/3)], {n, 0, 40}] (* _Vincenzo Librandi_, Jan 06 2014 *)
%o A018021 (Magma) [Floor(16^(n/3)): n in [0..40]]; // _Vincenzo Librandi_, Jan 06 2014
%Y A018021 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), this sequence (k=16), A018024 (k=17), A018027 (k=18), A018030 (k=19), A018033 (k=20), A018036 (k=21), A018039 (k=22), A018042 (k=23), A018045 (k=24).
%K A018021 nonn
%O A018021 0,2
%A A018021 _N. J. A. Sloane_
%E A018021 More terms from _Vincenzo Librandi_, Jan 06 2014