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A125722
Greatest product of two numbers made up together of decimal digits 0 to n once.
1
0, 20, 630, 13120, 224120, 3420020, 48460020, 651939020, 8439739020
OFFSET
1,2
EXAMPLE
The greatest product of two numbers using digits 0 through 7,for instance, occurs when the difference between them is least (since X*Y={(X+Y)^2 - (X-Y)^2}/4), i.e., when the product equals 7420*6531=48640020=a(7).
CROSSREFS
Sequence in context: A202577 A059420 A129906 * A336412 A226731 A201724
KEYWORD
fini,full,nonn,base
AUTHOR
Lekraj Beedassy, Feb 01 2007
EXTENSIONS
Edited by Charles R Greathouse IV, Aug 05 2010
STATUS
approved