OFFSET
1,3
COMMENTS
Construction rule is same as for box and Vicsek fractals, but uses 6 boxes at initial stage (n = 1) and has only one symmetrical axis. The scale factor of these fractals is 1/3. The actual tetraflake fractals have a scale factor of 1/2.
LINKS
Kival Ngaokrajang, Illustration of initial terms
Eric Weisstein's World of Mathematics, Box Fractal
Wikipedia, n-flake
Wikipedia, Vicsek Fractal
FORMULA
Floor((5*a(n-1)-2*(4*c(n-1)+3^(n-1)))/18) for n >1, a(1)=18, c(1)=1.
PROG
(PARI){a=18; c=1; print1(1, ", "); for (n=1, 50, c=4*c+3^(n-1); a=5*a-2*c; aa=floor((a*(1/3)^n)/18); print1(aa, ", ")); }
CROSSREFS
KEYWORD
nonn
AUTHOR
Kival Ngaokrajang, Apr 20 2014
STATUS
approved