A359867 a(n) is the number of k > 0 such that n-1-2*k >= 0 and a(n-1-2*k) >= a(n-1-k) + a(n-1).

0, 0, 0, 1, 0, 1, 1, 0, 3, 0, 2, 1, 1, 3, 0, 4, 0, 4, 1, 1, 2, 1, 3, 0, 6, 0, 7, 0, 8, 0, 6, 2, 1, 7, 0, 8, 0, 10, 0, 9, 1, 7, 2, 4, 4, 2, 7, 1, 11, 0, 15, 0, 13, 1, 9, 2, 7, 3, 4, 7, 2, 12, 0, 18, 0, 18, 1, 11, 2, 9, 3, 7, 5, 5, 6, 4, 7, 3, 10, 1, 15, 0, 19

Offset

0,9

Links

Rémy Sigrist, Table of n, a(n) for n = 0..10000

Rémy Sigrist, Scatterplot of the first 250000 terms

Rémy Sigrist, C program

Example

The first terms, alongside the corresponding k's, are:
  n   a(n)  k's
  --  ----  ------------
   0     0  {}
   1     0  {}
   2     0  {}
   3     1  {1}
   4     0  {}
   5     1  {2}
   6     1  {1}
   7     0  {}
   8     3  {1, 2, 3}
   9     0  {}
  10     2  {2, 3}
  11     1  {1}
  12     1  {4}
  13     3  {1, 2, 3}
  14     0  {}
  15     4  {2, 3, 5, 7}

Prog

(C) See Links section.

Crossrefs

Cf. A359866.

Sequence in context: A181786 A164629 A100950 * A021335 A089595 A238133

Adjacent sequences: A359864 A359865 A359866 * A359868 A359869 A359870

Keyword

nonn

Author

Rémy Sigrist, Jan 16 2023

Status

approved