Hi Jon,
Thanks for this info. I noticed that RMP 56 is a seked problem with a pyramid baselength of 360 cubits and a height of 250 cubits. The answer is seked 5 1/25 or five palms and 1/25th of a palm. This translates to 54 deg 14', which is oddly the precise angle for the lower part of the bent given by Perring, before the RMP was discovered and before sekeds were considered as a possible basis for the slopes of the pyramids. This does not seem to be a particularly practical seked, suggesting to me that while the slopes of pyramids may be expressed as sekeds, they may not have been built based on a consideration of the practical utility of a seked slope facilitating the measurement and placement of the blocks and courses of the pyramid under construction. I agree with Stadelman, Dorner and Legon that the baselength of the bent is 362 cubits (or 361.8 cubits) based on the great pyramid cubit, but several researchers, including Petrie, thought the intended base length of the bent was 360 cubits, with a slightly longer cubit. This would conform to the baselength of the pyramid in RMP 56.