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 A212455 #22 Jan 20 2024 11:27:10
%S A212455 1,5,10,16,23,29,36,44,52,59,68,76,84,93,102,110,119,129,138,147,156,
%T A212455 166,176,185,195,205,215,225,235,245,255,266,276,286,297,307,318,329,
%U A212455 339,350,361,372,383,394,404,416,427
%N A212455 a(n) = floor(2n*log(2n)).
%H A212455 Vincenzo Librandi, <a href="/A212455/b212455.txt">Table of n, a(n) for n = 1..1000</a>
%t A212455 Table[Floor[2*n*Log[2*n]], {n, 60}] (* _Vincenzo Librandi_, Feb 13 2013 *)
%o A212455 (Derive) PROG(y := [], x := 100, LOOP(IF(x = 0, RETURN y), y := ADJOIN(FLOOR(2·x·LOG(2·x)), y), x := x - 1))
%o A212455 (Magma) [Floor(2*n*Log(2*n)): n in [1..80]]; // _Vincenzo Librandi_, Feb 13 2013
%o A212455 (PARI) a(n)=2*n*log(2*n)\1 \\ _Charles R Greathouse IV_, Sep 04 2015
%Y A212455 Cf. A050502, A050504, A212456, A212457, A212458, A212459, A212460, A212461, A212462.
%K A212455 easy,nonn
%O A212455 1,2
%A A212455 _Mohammad K. Azarian_, May 31 2012