Euler Factorization For The Fifth Fermat number

Published On :2021-06-14 20:00:00

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[begin{array}{l} {F_5} = {2^{{2^5}}} + 1 = 4294967297\\ The{rm{ }}Fermat{rm{ }}number;{F_5};is{rm{ }}divisible{rm{ }}by{rm{ }}641.\\ Proof:\\ {F_5} = {2^{32}} + 1 = {2^{18}} * {2^{14}} + 1\\ = 262144 * {2^{14}} + 1 = 261735 * {2^{14}} + 409 * {2^{14}} + 1\\ = 261735 * {2^{14}} + 52352 * {2^7} + 1\\ = 5 * 52347 * {2^{14}} + left( {5 + 52347} right) * {2^7} + 1\\ = left( {5 * {2^7} + 1} right)left( {52347 * {2^7} + 1} right) = 641 * 6700417.\\ Which{rm{ }}gives;641;|;{F_5}\ end{array}]