3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $i = 1; for($f = 0; $f <= 20; $f++) { echo "F".$f." = ".($i+pow($f,$i-1))."\n"; $i++; }
based on jjE63
Output for 4.3.6 - 5.6.28, hhvm-3.12.0, 7.0.0 - 7.1.0
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 hhvm-3.10.0

Process exited with code 153.
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