A152458 Numbers k that A064413(k) = k.

1, 2, 8, 40, 64

Offset: 1

Author

Artur Jasinski, Dec 05 2008

Keywords

• nonn
• more

Comments

Conjecture: This sequence is finite.

Contribution from Artur Jasinski, Dec 08 2008: (Start)

The EKG sequence A064413 has 3 critical lines.

Numbers which belong to the critical lines:

(1) A064413(k) = k see this sequence,

(3/2) 2*A064413(k) = 3*k see A152519,

(1/2) 2*A064413(k) = k has only 2 numbers {10, 14}.

Because points are concentrated on the plot of EKG sequence near these 3 critical lines, the number of points belonging to critical lines is surprisingly low.

Is this sequence complete? (End)

Also fixed points of A247379. - Reinhard Zumkeller, Sep 15 2014

a(6) > 10^5, if it exists. - Amiram Eldar, Oct 23 2024

Crossrefs

Cf. A064413, A152519, A247379.

Programs

Haskell

a152458 n = a152458_list !! (n-1)
a152458_list = [x | x <- [1..], a064413 x == x]
-- Reinhard Zumkeller, Sep 15 2014