SPSR from orders 9 to 17 are sorted by percentage of primes in elements. o9-17spsr-prime.csv
format; "Order" "Width" "Height" "E1" ... "E17" (bouwkamp codes) "P1" ... "P17"(binary 1 if prime, 0 if not) "Prime Total" "Percent of elements prime"
The maximum proportion of primes among the elements of squared rectangles, up to order 17 is 64.71% (11/17) for a 260 x 258 rectangle. This is significantly higher than the proportion found in squared squares. Among squared squares, 2 examples are known of 50% prime.