The Nth Item

Topic link: https: //nanti.jisuanke.com/t/41355

Outline of Solution: This question is in fact very simple idea, is determined every n- _{. 1} with the calculated into F. (N- _{. 1} ), then n- ₂ is n- _{. 1}  XOR F. (N- _{. 1} ) ² , wherein the time limit is 1000ms key;

The title quadratic residue theorem + inversing the speed of light power +

Using the quadratic residue theorem + inversing can convert the equation as F (n-) = 559 329 360 (262 199 973 ^n- -736 044 383 ^n- ) 998 244 353%

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