take NAT --> 0c ; :: thesis: NAT --> 0c is summable
take 0c ; :: according to COMSEQ_2:def 5,COMSEQ_3:def 8 :: thesis: for b1 being object holds
( b1 <= 0 or ex b2 being set st
for b3 being set holds
( not b2 <= b3 or not b1 <= |.(((Partial_Sums (NAT --> 0c)) . b3) - 0c).| ) )

let p be Real; :: thesis: ( p <= 0 or ex b1 being set st
for b2 being set holds
( not b1 <= b2 or not p <= |.(((Partial_Sums (NAT --> 0c)) . b2) - 0c).| ) )

assume A1: 0 < p ; :: thesis: ex b1 being set st
for b2 being set holds
( not b1 <= b2 or not p <= |.(((Partial_Sums (NAT --> 0c)) . b2) - 0c).| )

take 0 ; :: thesis: for b1 being set holds
( not 0 <= b1 or not p <= |.(((Partial_Sums (NAT --> 0c)) . b1) - 0c).| )

for n being Nat holds (NAT --> 0c) . n = 0c ;
hence for b1 being set holds
( not 0 <= b1 or not p <= |.(((Partial_Sums (NAT --> 0c)) . b1) - 0c).| ) by A1, Th24, COMPLEX1:44; :: thesis: verum