▁on ▁ 1 ▁July ▁ 1 9 9 6 , ▁Kn uth ▁sent ▁out ▁more ▁than ▁ 2 5 0 ▁letters , ▁ 1 2 5 ▁of ▁which ▁contained ▁checks , ▁for ▁errors ▁reported ▁in ▁The ▁Art ▁of ▁Computer ▁Program ming ▁since ▁the ▁summer ▁of ▁ 1 9 8 1 . ▁A ▁few ▁of ▁these ▁remain ▁un c laimed ▁as ▁of ▁May ▁ 2 0 0 6 . ▁When ▁Kn uth ▁is ▁not ▁able ▁to ▁reply ▁immediately , ▁he ▁adds ▁ 5 % ▁interest , ▁comp ounded ▁continu ously , ▁to ▁the ▁reward . ▁ ▁See ▁also ▁▁ ▁List ▁of ▁computer - related ▁awards ▁ ▁Erd ős ' s ▁problems ▁ ▁References ▁ ▁External ▁links ▁The ▁Bank ▁of ▁San ▁Ser rif fe ▁Inter view ▁( Real Video ▁format ) ▁( or ▁Trans cript ) ▁with ▁Kn uth ▁on ▁National ▁Public ▁Radio ▁ ▁Category : Ch allenge ▁awards ▁Category : Comput er - related ▁awards ▁Category : Donald ▁Kn uth <0x0A> </s> ▁Howard ▁Be har ▁is ▁former ▁president ▁of ▁Star bu cks ▁C off ee ▁Company ▁International ▁and ▁the ▁author ▁of ▁It ' s ▁Not ▁About ▁The ▁C off ee : ▁Le ad ership ▁Princi ples ▁from ▁a ▁Life ▁at ▁Star bu cks . ▁ ▁He ▁started ▁working ▁at ▁Star bu cks ▁in ▁ 1 9 8 9 ▁when ▁the ▁company ▁had ▁just ▁begun ▁to ▁vent ure ▁outside ▁the ▁American ▁north west ▁region . ▁Initial ly ▁serving ▁as ▁vice ▁president ▁of ▁sales ▁and ▁operations , ▁he ▁grew ▁the ▁ret ail ▁business ▁from ▁ 2