A352999 a(n) is the least k > 0 such that A109812(n) and A109812(n + 2*k) have different binary lengths.
1, 2, 1, 1, 2, 1, 1, 1, 1, 3, 2, 2, 1, 1, 1, 1, 2, 1, 1, 1, 4, 2, 3, 1, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 2, 2, 1, 1, 1, 1, 3, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 1, 1, 1, 4, 1, 3, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 1, 8
Offset: 1
Examples
For n = 21:
- we have:
k bin(A109812(21+2*k))
- --------------------
0 100100
1 101000
2 100010
3 110000
4 1000000
- so a(21) = 4.
Links
- Rémy Sigrist, Scatterplot of the first million terms
- Rémy Sigrist, C++ program
Formula
a(n) <= A352998(n).