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 A192572 #6 Mar 30 2012 18:55:30
%S A192572 1,0,1,1,2,5,9,20,44,101,239,584,1468,3789,10027,27161,75211,212651,
%T A192572 613228,1801879,5390071,16401436,50730640,159393146,508408373,
%U A192572 1645330314,5399614435,17960973056,60528130675
%N A192572 a(n) = sum((-1)^(n-k)*floor(sqrt(Bell(k))),k=0..n).
%t A192572 Table[Sum[(-1)^(n-k)Floor[Sqrt[BellB[k]]],{k,0,n}],{n,0,100}]
%o A192572 (Maxima) makelist(sum((-1)^(n-k)*floor(sqrt(belln(k))),k,0,n),n,0,28);
%Y A192572 Cf. A000110, A192570, A192571.
%K A192572 nonn
%O A192572 0,5
%A A192572 _Emanuele Munarini_, Jul 04 2011