A1: 2 |^ (1 + 1) = (2 |^ 1) * 2 by NEWTON:6;
then 2 |^ (2 + 1) = 4 * 2 by NEWTON:6;
then A2: 2 |^ (2 + 3) = 4 * 8 by A1, NEWTON:8;
A3: 2 |^ (2 + 2) = 4 * 4 by A1, NEWTON:8;
then 2 |^ (4 + 4) = 16 * 16 by NEWTON:8;
then A4: 2 |^ (8 + 8) = 256 * 256 by NEWTON:8;
A5: 2 |^ (16 + 16) = (2 |^ 16) * (2 |^ 16) by NEWTON:8;
( Fermat 5 = (2 |^ (2 |^ 5)) + 1 & Fermat 4 = (2 |^ (2 |^ 4)) + 1 ) by PEPIN:def 3;
hence ( Fermat 5 = (2 |^ 32) + 1 & (2 |^ 32) + 1 = 641 * 6700417 & 6700417 > Fermat 4 ) by A3, A2, A4, A5; :: thesis: verum