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A271448
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Numbers which are the sum of their proper divisors containing the digit 2.
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8
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OFFSET
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1,1
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COMMENTS
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a(7) > 10^12.
For each digit d=0..9 there is a corresponding sequence in the OEIS (see Crossrefs), except for d=1, because up to 10^12, only 2654635632 is equal to the sum of its proper divisors which contain the digit 1.
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LINKS
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EXAMPLE
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The proper divisors of 546 are 1, 2, 3, 6, 7, 13, 14, 21, 26, 39, 42, 78, 91, 182, and 273. Since 2+21+26+42+182+273 = 546, 546 is a term.
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MATHEMATICA
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Select[Range[10^6], # == Plus @@ Select[Most@ Divisors@#, MemberQ[ IntegerDigits@ #, 2] &] &]
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CROSSREFS
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KEYWORD
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nonn,base,less,more
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AUTHOR
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STATUS
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approved
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