An alternative 42-term sum

Using the substitution

/ 15 + / 30 + / 90 = / 18 + / 24 + / 72

gives the alternative sum

\begin{array}{rcl} 1 & = & / 17 + / 18 + / 20 + / 21 + / 22 + / 24 + / 26 + / 27 + / 32 + / 33 \\ + & / 34 + / 35 + / 36 + / 38 + / 39 + / 40 + / 42 + / 44 + / 45 + / 48 \\ + & / 50 + / 52 + / 54 + / 55 + / 56 + / 60 + / 63 + / 66 + / 70 + / 72 \\ + & / 75 + / 76 + / 77 + / 80 + / 84 + / 85 + / 88 + / 90 + / 91 + / 95 \\ + & / 96 + / 99. \end{array}