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 A210543 #9 Feb 02 2022 12:23:10
%S A210543 1,1,1,1,1,1,2,4,8,16,32,64,129,267,582,1364,3454,9338,26429,76929,
%T A210543 227579,680113,2050000,6242818,19284165,60754153,196341570,654012814,
%U A210543 2251195713,8005274899,29325473071,110181281435,422565983725
%N A210543 Number of arrays of n nonnegative integers with value i>0 appearing only after i-1 has appeared at least 6 times.
%H A210543 R. H. Hardin, <a href="/A210543/b210543.txt">Table of n, a(n) for n = 1..210</a>
%F A210543 a(n) = 1 if n<=6 else Sum_{i=0..n-6} (binomial(n-6,i)*a(i)).
%e A210543 Some solutions for n=17
%e A210543 ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
%e A210543 ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
%e A210543 ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
%e A210543 ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
%e A210543 ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
%e A210543 ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
%e A210543 ..0....1....1....1....0....0....1....1....1....0....1....1....1....1....0....0
%e A210543 ..1....0....0....1....0....1....1....1....1....1....0....1....0....1....1....1
%e A210543 ..0....0....0....1....1....1....1....0....1....1....1....0....1....1....1....1
%e A210543 ..1....1....1....0....0....1....0....1....1....1....1....0....1....0....1....1
%e A210543 ..0....0....1....1....0....1....1....1....0....0....0....0....0....1....1....1
%e A210543 ..1....1....1....1....1....1....1....1....1....1....1....1....1....1....1....0
%e A210543 ..0....1....0....0....1....0....0....1....1....1....1....1....1....1....1....0
%e A210543 ..1....1....0....1....0....1....0....1....2....1....1....1....1....0....0....1
%e A210543 ..1....0....0....1....1....0....1....0....2....1....0....0....0....0....1....1
%e A210543 ..1....0....1....1....0....0....2....1....0....1....0....0....0....0....1....1
%e A210543 ..2....0....1....0....1....0....1....1....2....0....0....1....2....1....2....0
%Y A210543 Column 6 of A210545.
%K A210543 nonn
%O A210543 1,7
%A A210543 _R. H. Hardin_, formula proved by _R. J. Mathar_ in the Sequence Fans Mailing List, Mar 22 2012