While looking through a used book I bought (Fractals Images of Chaos by Hans Lauwerier) I saw a formula I wasn't familiar with. The formula was discovered in 1969 by French mathematician M. Henon. I entered it into Fracton, played with it a bit, and found a few fractals I liked. Henon is listed in FractInt's built in formula list but I have never seen anyone use it. I have no way to tell if FractInt's Henon is the same as this one. Here is a page with an image: http://www.fracton.org/fmlposts/henon_jko.html Here is the par file used to generate the fractal: Henon_JKO { ; Exported from Fracton. reset=2004 type=formula formulafile=fracton.frm formulaname=F_20101115_0906 passes=1 float=y center-mag=0.32/0.15/0.53333334/1/0/0 params=-0.0235/0.488/4.6/0/0/0/0/0/0/0 maxiter=190 proximity=0 colors=000aaateOthNtjNtlMtnMtoLtqLtsKtuKswJswJsvJs\ uJsuJstJssJssJsrKsqKspKspKsoKsnKsnKsmKslLslLskLsjL\ siLsiLshLsgLsgMsfMseMseMsdMscMsbMsbMsaNs`Ns`Ns_NsZ\ NsZNsYNsXNsWOsWOsVOsUOsUOsTOsSOsSOsRPsQPsPPsPPsOPs\ NPsNPsMPsLQsLQsKQsJQsIQsIQsHQsGQsGRsFRsERsERsDRsCR\ sBRsBRsASs9Ss9Ss8Ss7Ss7Ss6Ss5Sr4Tq4Tp4To5Tn5Sl6Sk6\ Sj7Si7Rh8Rf8Re9Rd9QcAQbAQ`BQ_BPZCPYCPWDOWDOWDOWDOW\ DOWDOVDOVDOVDOVDOVDOUDOUDOUDOUDOUDOTDOTDOTDOTDOTDO\ TDOSDOSDOSDOSDOSDORCORCORCORCORCOQCOQCOQCOQCOQCOQC\ OPCOPCOPCPPCPPCPOCPOCPOCPOCPOCPNCPNCPNCPNCPNCPNCPM\ BPMBPMBPMBPMBPLBPLBPLBPLBPLBPKBPKBPKBPKBPKBPKBPJBP\ JBPJBPJBPJBPIBPIBPIBPIBPIBPHAQIBQJDQLEQMGQOHQPJQRK\ QSMQUNQVPQWQQYSQZTQ`VRaWRcYRdZRf`RgaRhcRjdRkfRmgRn\ iRpjRqlRsnSrnSpnSnnSmnSknSinSgnSfnTdnTbnTanT_nTYnT\ WnTVnTTnURnUQnUOnUMnUKnUJnUHnUFnVEnVCnVAnV8nV7nV5n\ V3nV1oW1oW1oW1oW1oW1pV1pV } frm:F_20101115_0906 { ; Henon's Expression ; From Fractals Images Of Chaos by Hans Lauwerier p126 ; x' = y ; y' = -x +2ay + by^2 ; Time = 0.4 sec at 640 x 480 with no anti-aliasing ; using Fracton on Mac Pro 2 x 2.8 GHz Quad-Core Xeon x=real(pixel),y=imag(pixel), a=2*real(p1),b=imag(p1),; p1 - Julia constant bailout=real(p2),; real p2 - bailout @beginloop, temp=y, y=a*y+b*y*y-x, x=temp, z=x+flip(y), |z|<=bailout } -- Mike Frazier www.fracton.org