Economical Numbers
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چکیده
A number n is said to be economical if the prime power factori-sation of n can be written with no more digits than n itself. We show that under a plausible hypothesis, related to the twin prime conjecture, there are arbitrarily long sequences of consecutive economial numbers, and exhibit such a sequence of length 9.
منابع مشابه
On strings of consecutive economical numbers of arbitrary length
In 1995, Bernardo Recamán Santos [4] defined a number n to be equidigital if the prime factorization of n requires the same number of decimal digits as n, and economical if its prime factorization requires no more digits. He asked whether there are arbitrarily long sequences of consecutive economical numbers. In 1998, Richard Pinch [2] gave an affirmative answer to this question assuming the pr...
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