The theory of numbers,p robablym ore than any other branch of
mathematicso, ffersp roblemst hat are verye asy to statea nd formulatceo mpletely,
b ut extremelyd ifficultto solve. There are manyt hat have baffled
even trainedw orkersi n this field,w ho have been obligedt o contentt hemselvesi
n manyc ases withb utp artialr esolutionos f theq uestions. These very
oftena ppear as isolated,a rtificiapl roblemsw hose solutionw oulda pparently
add veryl ittlet o the main body of theory. But sometimest herei s an historicali
nteresta ttached,w hich coupledw itha n allurings implicityo f formulationa
ttractsi nvestigatortso wardi t. There is alwayst hep ossibilityt,o o,
that the pursuito f solutionso f even these elusive problemsm ay lead to the
discoveryo f mathematicalr elations,o r processest hat are new and of much
moreg enerala pplicationt han to the immediatep roblemt o be solved.
Some such justificationm ay be necessaryf orr esearchc oncerningt he
existenceo r relationso f perfectn umbers. Indeed, Fermatw as led by this
problemt o some of his mosti mportantt heorems. It is moreovera problem
of muchh istorici nterest.