let p be prime odd Nat; :: thesis: for m being positive Nat
for k, j, i being Nat st p + 1 < i & i in dom (LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) holds
(LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) /. i = 0. (Polynom-Ring INT.Ring)

let m be positive Nat; :: thesis: for k, j, i being Nat st p + 1 < i & i in dom (LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) holds
(LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) /. i = 0. (Polynom-Ring INT.Ring)

let k, j be Nat; :: thesis: for i being Nat st p + 1 < i & i in dom (LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) holds
(LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) /. i = 0. (Polynom-Ring INT.Ring)

1 < p by INT_2:def 4;
then 1 + 1 <= p by INT_1:7;
then 2 - 2 <= p - 2 by XREAL_1:6;
then p - 2 in NAT by INT_1:3;
then reconsider p2 = p - 2 as Nat ;
reconsider n0 = j as Nat ;
set D = Der1 INT.Ring;
set PR = Polynom-Ring INT.Ring;
set f = Product (ff_0 (m,p));
set xj = tau j;
set yj = Product (Del ((ff_0 (m,p)),j));
reconsider u = (k choose p) * (((Der1 INT.Ring) |^ (k -' p)) . (Product (Del ((ff_0 (m,p)),j)))) as Element of the carrier of (Polynom-Ring INT.Ring) ;
A2: 1. (Polynom-Ring INT.Ring) = (Der1 INT.Ring) . (tau j) by Th27
.= ((Der1 INT.Ring) |^ 1) . (tau j) by VECTSP11:19
.= ((Der1 INT.Ring) |^ 1) . ((tau j) |^ 1) by BINOM:8 ;
len (LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) = k + 1 by RINGDER1:def 4;
then A3: dom (LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) = Seg (k + 1) by FINSEQ_1:def 3;
for i being Nat st p + 1 < i & i in dom (LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) holds
(LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) /. i = 0. (Polynom-Ring INT.Ring)
proof
let i be Nat; :: thesis: ( p + 1 < i & i in dom (LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) implies (LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) /. i = 0. (Polynom-Ring INT.Ring) )
assume A4: ( p + 1 < i & i in dom (LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) ) ; :: thesis: (LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) /. i = 0. (Polynom-Ring INT.Ring)
set u = (k choose (i -' 1)) * (((Der1 INT.Ring) |^ ((k + 1) -' i)) . (Product (Del ((ff_0 (m,p)),j))));
A5: ( 1 <= i & i <= k + 1 ) by A3, A4, FINSEQ_1:1;
(p + 1) - 1 < i - 1 by A4, XREAL_1:6;
then A7: p < i -' 1 by A5, XREAL_1:233;
(LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) . i = ((k choose (i -' 1)) * (((Der1 INT.Ring) |^ ((k + 1) -' i)) . (Product (Del ((ff_0 (m,p)),j))))) * (((Der1 INT.Ring) |^ (i -' 1)) . ((tau j) |^ p)) by A4, RINGDER1:def 4
.= ((k choose (i -' 1)) * (((Der1 INT.Ring) |^ ((k + 1) -' i)) . (Product (Del ((ff_0 (m,p)),j))))) * (0. (Polynom-Ring INT.Ring)) by A7, A2, E_TRANS1:21
.= 0. (Polynom-Ring INT.Ring) ;
hence (LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) /. i = 0. (Polynom-Ring INT.Ring) by A4, PARTFUN1:def 6; :: thesis: verum
end;
hence for i being Nat st p + 1 < i & i in dom (LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) holds
(LBZ ((Der1 INT.Ring),k,(Product (Del ((ff_0 (m,p)),j))),((tau j) |^ p))) /. i = 0. (Polynom-Ring INT.Ring) ; :: thesis: verum