let a be odd Nat; :: thesis: ( a > 1 implies for s being Nat st s is double_odd & (a |^ s) + 1 is double_odd & s divides (a |^ s) + 1 holds
( (a |^ s) + 1 > s & (a |^ s) + 1 is double_odd & (a |^ ((a |^ s) + 1)) + 1 is double_odd & (a |^ s) + 1 divides (a |^ ((a |^ s) + 1)) + 1 ) )

assume A1: a > 1 ; :: thesis: for s being Nat st s is double_odd & (a |^ s) + 1 is double_odd & s divides (a |^ s) + 1 holds
( (a |^ s) + 1 > s & (a |^ s) + 1 is double_odd & (a |^ ((a |^ s) + 1)) + 1 is double_odd & (a |^ s) + 1 divides (a |^ ((a |^ s) + 1)) + 1 )

let s be Nat; :: thesis: ( s is double_odd & (a |^ s) + 1 is double_odd & s divides (a |^ s) + 1 implies ( (a |^ s) + 1 > s & (a |^ s) + 1 is double_odd & (a |^ ((a |^ s) + 1)) + 1 is double_odd & (a |^ s) + 1 divides (a |^ ((a |^ s) + 1)) + 1 ) )
assume that
A2: s is double_odd and
A3: (a |^ s) + 1 is double_odd and
A4: s divides (a |^ s) + 1 ; :: thesis: ( (a |^ s) + 1 > s & (a |^ s) + 1 is double_odd & (a |^ ((a |^ s) + 1)) + 1 is double_odd & (a |^ s) + 1 divides (a |^ ((a |^ s) + 1)) + 1 )
consider j1 being odd Nat such that
A5: s = 2 * j1 by A2;
consider j2 being odd Nat such that
A6: (a |^ s) + 1 = 2 * j2 by A3;
consider j3 being Nat such that
A7: j1 = (2 * j3) + 1 by ABIAN:9;
consider m being Nat such that
A8: (a |^ s) + 1 = s * m by A4, NAT_D:def 3;
(a |^ s) + 1 = (2 * j1) * m by A5, A8;
then j2 = j1 * m by A6;
then m is odd ;
then consider z being Nat such that
A9: m = (2 * z) + 1 by ABIAN:9;
set s1 = (a |^ s) + 1;
1 + 1 <= a by A1, NAT_1:13;
then A10: a |^ s > s by NEWTON:86;
(a |^ s) + 0 < (a |^ s) + 1 by XREAL_1:8;
hence (a |^ s) + 1 > s by A10, XXREAL_0:2; :: thesis: ( (a |^ s) + 1 is double_odd & (a |^ ((a |^ s) + 1)) + 1 is double_odd & (a |^ s) + 1 divides (a |^ ((a |^ s) + 1)) + 1 )
thus (a |^ s) + 1 is double_odd by A3; :: thesis: ( (a |^ ((a |^ s) + 1)) + 1 is double_odd & (a |^ s) + 1 divides (a |^ ((a |^ s) + 1)) + 1 )
set q = ((((4 * j3) * z) + (2 * z)) + (2 * j3)) + 1;
a |^ (2 * (((((4 * j3) * z) + (2 * z)) + (2 * j3)) + 1)) = (a |^ (((((4 * j3) * z) + (2 * z)) + (2 * j3)) + 1)) |^ 2 by NEWTON:9;
hence (a |^ ((a |^ s) + 1)) + 1 is double_odd by A5, A7, A8, A9; :: thesis: (a |^ s) + 1 divides (a |^ ((a |^ s) + 1)) + 1
(a |^ s) + 1 divides ((a |^ s) |^ ((2 * z) + 1)) + (1 |^ ((2 * z) + 1)) by NEWTON01:35;
hence (a |^ s) + 1 divides (a |^ ((a |^ s) + 1)) + 1 by A8, A9, NEWTON:9; :: thesis: verum