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A226726
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Numbers n such that the product of its decimal digits (A007954) is between n/2-1 and n/2+1.
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0
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OFFSET
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1,2
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COMMENTS
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LINKS
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MATHEMATICA
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j[lis_] := Product[lis[[i]], {i, 1, Length[lis]}];
jj[n_] := j[RealDigits[n][[1]]]; Table[If[n/2 - 1 < j[RealDigits[n][[1]]] < n/2 + 1, n], {n, 1, 1000000}] // Union
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PROG
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(PARI) is(n)=my(d=digits(n)); abs(prod(i=1, #d, d[i])-n/2)<=1
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CROSSREFS
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KEYWORD
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nonn,fini,full,base
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AUTHOR
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STATUS
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approved
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