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<?php $i = 1; for($f = 0; $f <= 20; $f++) { echo "F".$f." = ".($i+pow($i,$f)-1)."\n"; $i++; }
based on 1o8Vv
Output for 4.3.6 - 7.1.0
F0 = 1 F1 = 3 F2 = 11 F3 = 67 F4 = 629 F5 = 7781 F6 = 117655 F7 = 2097159 F8 = 43046729 F9 = 1000000009 F10 = 25937424611 F11 = 743008370699 F12 = 23298085122493 F13 = 793714773254157 F14 = 29192926025390639 F15 = 1152921504606846991 F16 = 4.8661191875667E+19 F17 = 2.1859115597387E+21 F18 = 1.0412735029791E+23 F19 = 5.24288E+24 F20 = 2.7821842944695E+26
Output for 4.3.0 - 4.3.5
F0 = 1 F1 = 3 F2 = 11 F3 = 67 F4 = 629 F5 = 7781 F6 = 117655 F7 = 2097159 F8 = 43046729 F9 = 1000000009 F10 = 25937424611 F11 = 743008370699 F12 = 23298085122493 F13 = 793714773254157 F14 = 29192926025390638 F15 = 1152921504606846991 F16 = 4.8661191875667E+19 F17 = 2.1859115597387E+21 F18 = 1.0412735029791E+23 F19 = 5.24288E+24 F20 = 2.7821842944695E+26