Converting $A8B34_{16}$ to octal. According to online calculators $A8B34_{16}=2505464_{\ 8}$, yet I keep getting $2005464_{\ 8}$. I just want to know where I'm going wrong.

$A8B34_{16}=10( 16^4)+8( 16^3) + 11( 16^2) + 3( 16) + 4$
$=10(2^48^4)+8(2^38^3)+11(2^28^2)+6(8)+4$
$=160(8^4)+8^5+44(8^2)+6(8)+4$
$=(8^2+7[8])(8^4)+8^5+(5[8]+4)(8^2)+6(8)+4$
$=8^6+7(8^5)+8^5+5(8^3)+4(8^2)+6(8)+4$
$=2(8^6)+5(8^3)+4(8^2)+6(8)+4$
$=2005464_{\ 8}$

We are lucky here that $8$ and $16$ are powers of two. It suffices to break down the numbers into bits and regroup:
$$A8B34_{16}=1010,1000,1011,0011,0100_2$$
$$=10,101,000,101,100,110,100_2=2505464_8$$
