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5 April 2009
- 01:0001:00, 5 April 2009 diff hist +4 m Divisibility by 7 No edit summary
3 April 2009
- 01:5601:56, 3 April 2009 diff hist +2 Divisibility by 7 →Direct Proof
- 01:5501:55, 3 April 2009 diff hist +42 Divisibility by 7 →Direct Proof
- 01:4001:40, 3 April 2009 diff hist 0 Divisibility by 7 No edit summary
- 01:3801:38, 3 April 2009 diff hist −7 Divisibility by 7 No edit summary
- 01:3701:37, 3 April 2009 diff hist +1,015 N Divisibility by 7 New page: == Theorem == An integer <math>X</math> with <math>n</math> digits is divisible by 7 if and only if <math>\sum_{i=0}^{n-1} (3^i X_i)</math> is divisible by 7 == Direct Proof == {{begin-e...