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 March 31st, 2019, 10:45 AM #1 Newbie   Joined: Mar 2019 From: N.Ireland Posts: 5 Thanks: 0 Impossible thought 3 x 4 = 12... 7 x 8 = 56... Nb the sequence of digits... Is there any other combination of consecutive digits that produce an answer which itself is made up from consecutive digits... In these examples the answer is also the immediate precursors to the sequence of the multipliers ...coincidence?? Of course .... Is there a simple proof showing these are the only numbers ?
 March 31st, 2019, 11:03 AM #2 Senior Member   Joined: Aug 2012 Posts: 2,343 Thanks: 732 9 x 10 = 90.
 March 31st, 2019, 11:05 AM #3 Newbie   Joined: Mar 2019 From: N.Ireland Posts: 5 Thanks: 0 Vg... Nicely done... With some poetic licence
 March 31st, 2019, 11:51 AM #4 Newbie   Joined: Mar 2019 From: N.Ireland Posts: 5 Thanks: 0 Doh.... Forgot to say excluding 1 x ( n, n+ 1,n+2 ,n+3 ....... ) Last edited by Paulb; March 31st, 2019 at 12:22 PM.
 March 31st, 2019, 12:20 PM #5 Global Moderator   Joined: Dec 2006 Posts: 20,835 Thanks: 2162 78 × 79 = 6162
 March 31st, 2019, 12:23 PM #6 Newbie   Joined: Mar 2019 From: N.Ireland Posts: 5 Thanks: 0 Yes many answers with nice figures but not sequential...
 March 31st, 2019, 12:49 PM #7 Global Moderator   Joined: Dec 2006 Posts: 20,835 Thanks: 2162 Poetic licence allows me to use a number base of 100 instead of 10. As you didn't require the consecutive digits to be in ascending order, 7 × 6 × 5 = 210. Thanks from topsquark and Paulb
 March 31st, 2019, 12:55 PM #8 Newbie   Joined: Mar 2019 From: N.Ireland Posts: 5 Thanks: 0 Brilliant......

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