I roto i te 1887, haere Cesàro tata ki te kī i te whakamāramatanga o (C, n) tāpiritanga, engari i hoatu e ia he torutoru anake tauira. I roto i ngā, tāpiri ia 1 − 2 + 3 − 4 +..., ki te 1⁄4 i te tikanga e kia rephrased rite (C, n) engari kihai i tika rite taua i te wa. tautuhia e ia te tikanga (C, n) i roto i 1890 i roto i te tikanga ki te kī i tona taurangi e ko te Cauchy o te (C, n) raupapa-summable me te (C, m-summable) raupapa + m (C, n-summable 1) hua. pātai: i tautuhia e Cesàro aha tikanga?
nga tikanga (C, n)