{"app":{"locale":"en-GB"},"problem":{"content":"

A sequence is defined as:

g_k = 1, for 0 ≤ k ≤ 1999
g_k = g_k-2000 + g_k-1999, for k ≥ 2000.

Find g_k mod 20092010 for k = 10¹⁸.

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