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A038369
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Numbers n such that n = (product of digits of n) * (sum of digits of n).
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14
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OFFSET
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1,3
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REFERENCES
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David W. Wilson: the list is complete. Proof: One shows that the number of digits is at most 84 and then it is only necessary to consider numbers of the forms 2^i*3^j*7^k and 3^i*5^j*7^k.
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LINKS
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Table of n, a(n) for n=1..4.
Eric Weisstein's World of Mathematics, Sum-Product Number.
Eric Weisstein's World of Mathematics, Digit.
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EXAMPLE
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144 belongs to the sequence because 1*4*4=16, 1+4+4=9 -> 16*9=144
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MATHEMATICA
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pdsdQ[n_]:=Module[{idn=IntegerDigits[n]}, (Total[idn]Times@@idn)==n]; Select[Range[0, 150], pdsdQ] (* From Harvey P. Dale, Apr 23 2011 *)
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CROSSREFS
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n = A007953(n) * A007954(n).
Cf. A066282.
Sequence in context: A177348 A007251 A219443 * A066282 A066176 A025363
Adjacent sequences: A038366 A038367 A038368 * A038370 A038371 A038372
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KEYWORD
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nice,nonn,fini,base,full,bref,changed
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AUTHOR
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Felice Russo
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STATUS
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approved
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