let m be non zero Element of NAT ; :: thesis: Lucas (m + 1) >= Lucas m
thus Lucas (m + 1) >= Lucas m :: thesis: verum
proof
defpred S1[ Nat] means Lucas ($1 + 1) >= Lucas $1;
A1: for k being non zero Nat st S1[k] & S1[k + 1] holds
S1[k + 2]
proof
let k be non zero Nat; :: thesis: ( S1[k] & S1[k + 1] implies S1[k + 2] )
assume that
S1[k] and
S1[k + 1] ; :: thesis: S1[k + 2]
(Lucas (k + 2)) + (Lucas (k + 1)) = Lucas (k + 3) by Th13;
hence S1[k + 2] by NAT_1:12; :: thesis: verum
end;
A2: S1[2] by Th14, Th15;
A3: S1[1] by Th11, Th14;
for k being non zero Nat holds S1[k] from FIB_NUM2:sch 1(A3, A2, A1);
hence Lucas (m + 1) >= Lucas m ; :: thesis: verum
end;