Number magic
Recently I found all the 22 existing ways to put 0 to 9 in the equation of a product such that each number occurs exactly once. And here they are:
5694×3=17082
6819×3=20457
6918×3=20754
8169×3=24507
9168×3=27504
3907×4=15628
7039×4=28156
9127×4=36508
5817×6=34902
3094×7=21658
4093×7=28651
9304×7=65128
9403×7=65821
594×27=16038
495×36=17820
402×39=15678
396×45=17820
715×46=32890
367×52=19084
297×54=16038
927×63=58401
345×78=26910
Also, as an extension, did the same after excluding zero:
1738×4= 6952
1963×4= 7852
483×12= 5796
297×18= 5346
198×27= 5346
157×28= 4396
186×39= 7254
138×42= 5796
159×48= 7632
(Dedicated to all my friends who happened to call me a numero-maniac…)
Went through all numbers till 99999999 to find these:
Squares of sums:
(20+25)²=2025
(30+25)²=3025
(494+209)²=494209
(2450+2500)²=24502500
(2550+2500)²=25502500
(5288+1984)²=52881984
(6048+1729)²=60481729
Sums of squares:
12²+33²=1233
88²+33²=8833
990²+100²=990100
9412²+2353²=94122353
Syed Iddi Hasan