<prompt> Ikiwa fx frac1 x1 - 3x, f_1x ffx, f_2x ff_1x, na kwa ujumla f_nx ff_n-1x, kisha f_19933  <response>: f3 frac1 31 - 3cdot 3 -frac12. Kisha f_13 f-frac12 frac1 - frac121 3cdotfrac12 frac15, displaystyle f_23 ffrac15 frac1 frac151 - 3cdotfrac15 3 na f_33 f3 frac1 31 - 3cdot 3 - frac12.Inafuata mara moja kwamba mizunguko ya kazi na f_n3 -frac12 ikiwa n 3k, f_n3 frac15 ikiwa n 3k 1 na f_n3 3 ikiwa n 3k 2. Tangu 1993 3cdot 664 1, f_19933 frac15. 