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<?php $i = 1; for($f = 0; $f <= 20; $f++) { echo "F".$f." = ".($i+pow($f,$i-1))."\n"; $i++; }
Output for 4.3.6 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
F0 = 2 F1 = 3 F2 = 7 F3 = 31 F4 = 261 F5 = 3131 F6 = 46663 F7 = 823551 F8 = 16777225 F9 = 387420499 F10 = 10000000011 F11 = 285311670623 F12 = 8916100448269 F13 = 302875106592267 F14 = 11112006825558031 F15 = 437893890380859391 F16 = 1.844674407371E+19 F17 = 8.2724026188634E+20 F18 = 3.9346408075297E+22 F19 = 1.9784196556603E+24 F20 = 1.048576E+26
Output for 4.3.0 - 4.3.5
F0 = 2 F1 = 3 F2 = 7 F3 = 31 F4 = 261 F5 = 3131 F6 = 46663 F7 = 823551 F8 = 16777225 F9 = 387420499 F10 = 10000000011 F11 = 285311670623 F12 = 8916100448269 F13 = 302875106592267 F14 = 11112006825558031 F15 = 437893890380859408 F16 = 1.844674407371E+19 F17 = 8.2724026188634E+20 F18 = 3.9346408075297E+22 F19 = 1.9784196556603E+24 F20 = 1.048576E+26

preferences:
229.93 ms | 402 KiB | 311 Q