A354254 a(n) is the least m >= 0 such that n = f^k(m) for some k >= 0 (where f^k denotes the k-th iterate of A092391).

0, 1, 1, 1, 4, 1, 6, 1, 6, 6, 1, 6, 1, 13, 1, 15, 13, 1, 18, 1, 18, 21, 1, 23, 21, 1, 21, 23, 1, 21, 30, 1, 32, 21, 30, 21, 1, 37, 1, 39, 37, 1, 37, 39, 1, 37, 46, 1, 48, 37, 46, 51, 1, 46, 54, 1, 56, 46, 54, 56, 1, 46, 54, 63, 1, 1, 46, 1, 46, 63, 1, 71, 63

Offset

0,5

Links

Table of n, a(n) for n=0..72.

Formula

a(n) = n iff n = 0 or n belongs to A010061.

a(n) = 1 iff n belongs to A010062.

Example

The first terms, alongside f(n), are:
  n   a(n)  f(n)
  --  ----  ----
   0     0     0
   1     1     2
   2     1     3
   3     1     5
   4     4     5
   5     1     7
   6     6     8
   7     1    10
   8     6     9
   9     6    11
  10     1    12
  11     6    14
  12     1    14
  13    13    16
  14     1    17

Prog

(PARI) a = vector(73, n, n-1); for (n=0, #a-1, m=n+hammingweight(n); if (m<#a, a[1+m]=min(a[1+n], a[1+m]))); print (a)

Crossrefs

Cf. A010061, A010062, A092391, A179016.

Sequence in context: A144907 A185093 A010779 * A215619 A136706 A326478

Adjacent sequences: A354251 A354252 A354253 * A354255 A354256 A354257

Keyword

nonn,base

Author

Rémy Sigrist, May 21 2022

Status

approved