Question Number 127931 by A8;15: last updated on 03/Jan/21
Commented by talminator2856791 last updated on 04/Jan/21
$$\: \\ $$$$\:\mathrm{what}\:\mathrm{is}\:\mathrm{the}\:\mathrm{series}\:\mathrm{for}\:\mathrm{which}\:\mathrm{you}\:\mathrm{want}\:\mathrm{evaluate}? \\ $$
Commented by A8;15: last updated on 04/Jan/21
$$\mathrm{S}_{\mathrm{n}} \:\mathrm{and}\:\mathrm{a}_{\mathrm{n}} \: \\ $$
Commented by talminator2856791 last updated on 04/Jan/21
$$\:\mathrm{but}\:\mathrm{what}\:\mathrm{is}\:{t}_{{n}} ? \\ $$
Commented by talminator2856791 last updated on 04/Jan/21
$$\:\mathrm{cant}\:\mathrm{find}\:\mathrm{sum}\:\mathrm{if}\:{n}\mathrm{th}\:\mathrm{term}\:\mathrm{is}\:\mathrm{not}\:\mathrm{provided} \\ $$