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A116207
Numbers k such that k concatenated with k+7 gives the product of two numbers which differ by 5.
5
493, 607, 629, 757, 17927, 33247, 93869, 19467217, 31223879, 72757727, 13454739732766891651472740499, 40093333713615672956030023507, 48089152118689474641229584727, 66424317743191484432891678269
OFFSET
1,1
EXAMPLE
72757727//72757734 = 85298138 * 85298143, where // denotes concatenation.
KEYWORD
nonn,base
AUTHOR
Giovanni Resta, Feb 06 2006
STATUS
approved