A188639 Decimal expansion of length/width of a 2nd electrum rectangle.

3, 0, 5, 8, 9, 5, 9, 3, 6, 6, 9, 9, 2, 8, 2, 0, 4, 5, 4, 0, 7, 0, 0, 1, 9, 2, 0, 2, 9, 0, 8, 5, 3, 2, 4, 0, 6, 5, 3, 0, 5, 0, 5, 7, 5, 2, 5, 1, 9, 5, 6, 6, 7, 8, 1, 0, 9, 7, 3, 3, 0, 8, 8, 1, 3, 8, 8, 0, 0, 6, 0, 8, 5, 7, 5, 6, 5, 5, 6, 7, 6, 4, 1, 3, 3, 3, 5, 6, 2, 4, 7, 1, 7, 5, 2, 1, 0, 8, 6, 1, 9, 5, 7, 8, 3, 3, 0, 9, 9, 1, 5, 4, 1, 6, 2, 9, 3, 8, 5, 4, 4, 6, 5, 4, 4, 7, 6, 0, 1, 9

Offset: 1

Author

Clark Kimberling, Apr 06 2011

Keywords

• nonn
• cons

Comments

See A188619 for the definition of 2nd electrum rectangle. Briefly, it is a rectangle such that the removal of a silver rectangle from one end leaves a golden rectangle.

Links

• Clark Kimberling, A Visual Euclidean Algorithm, The Mathematics Teacher 76 (1983) 108-109.

Crossrefs

Cf. A188619, A188618, A188638.

Programs

Mathematica

t=1+3^(1/2); r=(t+(t^2+4)^(1/2))/2
FullSimplify[r]
N[r, 130]