MathDB

Suppose that a sequence

(a_n)_{n=1}^{\infty}

of integers has the following property: For all

n

large enough (i.e.

n \ge N

for some

N

a_n

equals the number of indices

i

1 \le i < n

, such that

a_i + i \ge n

. Find the maximum possible number of integers which occur infinitely many times in the sequence.

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