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A145746
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Numbers n such that sum of the proper divisors of n is product of digits of n.
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OFFSET
| 1,1
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COMMENTS
| All repunit primes are in the sequence. So A004022 is a subsequence of this sequence.
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EXAMPLE
| sigma(11735953)=sigma(883*13291)=11735953+(13291+883+1)=11735953+
1*1*7*3*5*9*5*3 so 11735953 is in the sequence.
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MATHEMATICA
| Do[If[DivisorSigma[1, n]-n==Apply[Times, IntegerDigits[n]], Print[n]], {n, 50000000}]
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CROSSREFS
| Cf. A004022.
Sequence in context: A136980 A083834 A136978 * A024267 A028584 A084342
Adjacent sequences: A145743 A145744 A145745 * A145747 A145748 A145749
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KEYWORD
| base,more,nice,nonn
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AUTHOR
| Farideh Firoozbakht (mymontain(AT)yahoo.com), Oct 27 2008
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