OFFSET
0,3
COMMENTS
There are 8^n level n squares on a Sierpinski carpet.
The terms of this sequence have a common factor 4.
Lim_{n->infinity} a(n)/a(n-1) = 8.
Lim_{n->infinity} a(n)/8^n = 0.73872777586247800994....
LINKS
Yi Yang, Table of n, a(n) for n = 0..32
Chyanog, Illustration of initial terms (the red squares are counted)
Wayne, Ickiverar, The C++ code generating the sequence
CROSSREFS
KEYWORD
nonn
AUTHOR
Yi Yang, Oct 04 2017
STATUS
approved