A065758 Numbers m that minimize | k /(k- EulerPhi(k)) - golden ratio phi | when k runs over all the numbers with the same number of digits as m.

6, 10, 20, 40, 50, 80, 230, 460, 920, 5278, 10556, 21112, 36946, 42224, 68614, 73892, 84448, 136390, 272780, 545560, 681950, 6718090, 10635086, 21270172, 42540344, 74445602, 85080688, 478006930, 956013860

Offset

1,1

Comments

Dual to A065657.

Links

Table of n, a(n) for n=1..29.

Joseph L. Pe, On Approximate Harmonic Division of n by phi(n) [Dead link]

Example

abs(10/(10-phi(10))) = 0.0486237 (approximately) is minimal for 2-digit numbers.
abs(460/(460-phi(460))) = 0.00168432 (approximately) is minimal for 3-digit numbers.

Crossrefs

Cf. A001622, A000010, A065657.

Sequence in context: A362183 A153369 A107981 * A348838 A254028 A085274

Adjacent sequences: A065755 A065756 A065757 * A065759 A065760 A065761

Keyword

nonn,more

Author

Joseph L. Pe, Dec 04 2001

Extensions

a(18)-a(29) from Sean A. Irvine, Sep 12 2023

Status

approved