9 8 . ▁ ▁As ▁of ▁ 2 0 0 9 ▁they ▁lived ▁in ▁Bar rh aven , ▁Ontario . ▁He ▁was ▁diagn osed ▁with ▁g astr ic ▁cancer ▁on ▁ 7 ▁March ▁ 2 0 1 5 , ▁at ▁the ▁age ▁of ▁ 6 5 ▁years . ▁ ▁He ▁died ▁at ▁home ▁with ▁L ise ▁on ▁ 2 5 ▁May ▁ 2 0 1 5 . ▁ ▁References ▁ ▁External ▁links ▁Legisl ative ▁Assembly ▁of ▁North west ▁Territ ories ▁list ▁of ▁premiers ▁ ▁Category : M embers ▁of ▁the ▁Legisl ative ▁Assembly ▁of ▁the ▁North west ▁Territ ories ▁Category : P rem iers ▁of ▁the ▁North west ▁Territ ories ▁Category : Pe ople ▁from ▁Y ellow kn ife ▁Category : Pe ople ▁from ▁Rost h ern , ▁S ask atch ew an ▁Category : 1 9 4 9 ▁birth s ▁Category : 2 0 1 5 ▁death s <0x0A> </s> ▁In ▁number ▁theory , ▁V ant ieg h ems ▁theorem ▁is ▁a ▁prim ality ▁criter ion . ▁It ▁states ▁that ▁a ▁natural ▁number ▁n ▁is ▁prime ▁if ▁and ▁only ▁if ▁ ▁Similarly , ▁n ▁is ▁prime , ▁if ▁and ▁only ▁if ▁the ▁following ▁con gru ence ▁for ▁polynomials ▁in ▁X ▁holds : ▁ ▁or : ▁ ▁Example ▁ ▁Let ▁n = 7 ▁forming ▁the ▁product ▁ 1 * 3 * 7 * 1 5 * 3 1 * 6 3 ▁= ▁ 6 1 5 1 9 5 . ▁▁ 6 1 5 1 9 5 ▁= ▁ 7 ▁mod ▁ 1