The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1
 0  X  0  0  X  X a*X a^2*X a^4*X a^5*X a^5*X  X a^5*X a^6*X  0 a*X a^5*X a*X a^5*X a^6*X a^6*X a^2*X a*X a*X  0 a^3*X a^4*X a^5*X a^3*X a^2*X a^5*X  0 a^6*X a^4*X a^4*X a^2*X a^3*X a^5*X a^4*X a^2*X  X a^6*X a^5*X a^3*X  0 a^4*X a*X a^3*X a^3*X a^3*X a*X a^4*X a*X a^3*X a*X  0  0 a^6*X a^4*X  X  0
 0  0  X  0 a^6*X a^5*X a*X a^6*X a^6*X a*X a^6*X a^2*X a*X a^3*X  X a^5*X a^3*X a^4*X a^4*X  X a^4*X  0  X a*X a*X a^6*X  0 a^3*X a^6*X  X a^2*X a^6*X a*X a^5*X  0 a*X a*X a^2*X a^6*X a^3*X a*X  0 a^5*X a^4*X a^4*X  0 a^6*X a^4*X a^5*X  X a^4*X a^2*X a^5*X a^6*X  0 a*X a^2*X  X  X  0 a^2*X
 0  0  0  X  X a^4*X a^4*X  X a^6*X a^4*X a^6*X a^6*X a^3*X a*X a^4*X a*X  0  0 a^6*X a^5*X a^6*X a^5*X a^5*X  X  X  X a^5*X a*X  0 a^4*X a^4*X a*X  X a*X  0 a^5*X a*X a^5*X a^5*X a^4*X a^4*X a*X  0 a^2*X a*X a^3*X a^3*X  0 a^3*X  X  X a^4*X a^3*X a^3*X a^2*X a^3*X a^2*X  X a^4*X a^3*X a^3*X

generates a code of length 61 over F8[X]/(X^2) who´s minimum homogenous weight is 400.

Homogenous weight enumerator: w(x)=1x^0+308x^400+756x^408+749x^416+595x^424+28672x^427+518x^432+315x^440+329x^448+175x^456+238x^464+49x^472+49x^480+14x^488

The gray image is a linear code over GF(8) with n=488, k=5 and d=400.
This code was found by Heurico 1.16 in 0.64 seconds.