Don't forget: the A paper sizes do NOT have proportions exactly 1.414... (sqrt(2))
The exact sizes in mm are....
{approx inch equiv)
2A0 1,189 x 1,682 mm 46,8 x 66,2 in
A0 841 x 1189 mm 33.1 x 46.8 in
A1 594 x 841 mm 23.4 x 33.1 in
A2 420 x 594 mm 16.5 x 23.4 in
A3 297 x 420 mm 11.7 x 16.5 in
A4 210 x 297 mm 8.3 x 11.7 in
A5 148 x 210 mm 5.8 x 8.3 in
A6 105 x 148 mm 4.1 x 5.8 in
A7 74 x 105 mm 2.9 x 4.1 in
The ratios of these from one to the next lower are...
1.41463414634146
1.41379310344828
1.41582491582492
1.41428571428571
1.41414141414141
1.41428571428571
1.41891891891892
1.40952380952381
1.34615384615385
sqrt(2) is 1.4142135623731
On the whole, the proportions are surprisingly close to sqrt(2).

Rodger Whitlock
Victoria, British Columbia, Canada
Maritime Zone 8, a cool Mediterranean climate
on beautiful Vancouver Island
