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Hofstadter-Conway \$10000 sequence is defined by nested recurrence relation $$c(n) = c(c(n-1)) + c(n-c(n-1))$$ with $c(1) = c(2) = 1$. This sequence is https://oeis.org/A004001 and it is well-known that this sequence has many amazing properties: https://www.sciencedirect.com/science/article/pii/0012365X9400303Z

A related curious sequence can be defined by similar recurrence relation as below $$c^*(n) = n - c^*(c^*(n-1)) - c^*(n-c^*(n-1))$$ with $c^*(1) = c^*(2) = 1$. I introduced this sequence in https://oeis.org/A287422 and recurrence is also investigated in terms of sensitivity of initial conditions selections: https://link.springer.com/chapter/10.1007%2F978-3-030-35441-1_14

Question. Can someone show that $c(n) - \frac{n}2$ $\ge$ $\left\lvert c^*(n) - \frac{n}2 \right\rvert$ for all $n \ge 1$ ? (It is checked up to $2^{30}$.)

(I share below graph in order to display behaviours of both sequences for $n \le 2^{10}$.
Red: $c(n) - \frac{n}2$, Black: $c^*(n) - \frac{n}2$)

enter image description here

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