let X be non empty MetrSpace; :: thesis: for x being Element of X
for S being sequence of X st S is_convergent_in_metrspace_to x holds
S is convergent

let x be Element of X; :: thesis: for S being sequence of X st S is_convergent_in_metrspace_to x holds
S is convergent

let S be sequence of X; :: thesis: ( S is_convergent_in_metrspace_to x implies S is convergent )
assume A1: S is_convergent_in_metrspace_to x ; :: thesis: S is convergent
take x ; :: according to TBSP_1:def 2 :: thesis: for b1 being Element of REAL holds
( b1 <= 0 or ex b2 being Element of NAT st
for b3 being Element of NAT holds
( not b2 <= b3 or not b1 <= dist ((S . b3),x) ) )

thus for b1 being Element of REAL holds
( b1 <= 0 or ex b2 being Element of NAT st
for b3 being Element of NAT holds
( not b2 <= b3 or not b1 <= dist ((S . b3),x) ) ) by A1, Def8; :: thesis: verum