#PDF memorial tribute to Richard K. Guy after he died at 103. He’s the guy who did the single-scale nomogram and discovered the glider in Life. #nomography
on 02026-01-11#paper about a “single-scale nomogram” by Richard K. Guy from 01953. The Mathematical Gazette, Vol. 37, No. 319 (Feb. 1953), p. 39, DOI: 10.2307/3609499. Using almost an #elliptic-curve and a straightedge to multiply, divide, and extract square roots. #Analog computation. The explanation of why it works uses elementary algebra: “Since the equation x³ + ax + b = 0 has zero for the sum of its roots, the x-coordinates of the three intersections of the line y = mx + c and the curve y = x³ + px + q add to zero.” #nomography #math
on 02026-01-10another #elliptic-curve nomogram, with some historical notes. #nomography #math
on 02022-02-09#Elliptic-curve nomogram calculator, similar to Guy’s 01953 “single-scale nomogram” but actually different #nomography #math
on 02022-02-09“A Single-Scale Nomogram”, from Richard K. Guy, The Mathematical Gazette, Vol. 37, No. 319 (Feb. 1953), p. 39, DOI: 10.2307/3609499. Using an #elliptic-curve and a straightedge to multiply, divide, and extract square roots. #Analog computation. The explanation of why it works uses elementary algebra. #nomography #math
on 02016-08-12