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A235812
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a(n) is the start of the earliest run of n numbers such that the sum of their digits is equal to the sum of the digits of their prime factors.
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0
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OFFSET
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1,1
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COMMENTS
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This sequence takes into account both primes and Smith numbers (A006753).
a(10) > 5*10^12.
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LINKS
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EXAMPLE
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The four numbers 2, 3, 4, 5 are either prime (2, 3, 5) or Smith (4) numbers. In any case, the sum of their digits is equal to the sum of their prime factors (counted with multiplicity), hence a(1) = a(2) = a(3) = a(4) = 2.
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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