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A113761
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Numbers n such that the number of divisors of n equals both the sum and the product of digits of n in base 10.
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0
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1, 2, 22, 2114, 11222, 21122, 22211, 112116, 121116, 1111143, 1413111, 3411111, 11111128, 11111821, 11112118, 11121231, 11811112, 13111212, 18111112, 21111118, 21111181, 21121113, 23111121, 111112119, 111119211, 192111111
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Intersection of A074312 and A057531.
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EXAMPLE
| 2114 belongs since 2+1+1+4=2*1*1*4=8 and 2114 has 8 divisors, {1, 2, 7, 14, 151, 302, 1057, 2114}.
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MATHEMATICA
| L={}; Do[d=IntegerDigits@n; p=Times@@d; If[p==Plus@@d && p==DivisorSigma[0, n], AppendTo[L, n]; Print[n]], {n, 1000000}]; L
lst = {}; fQ[n_] := (id = IntegerDigits@n; Plus @@ id == Times @@ id == DivisorSigma[0, n]); Do[ If[ fQ@n, AppendTo[lst, n]], {n, 2*10^8}]; lst
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CROSSREFS
| Cf. A034710, A057531, A074312.
Sequence in context: A193486 A054948 A104149 * A054349 A113930 A181235
Adjacent sequences: A113758 A113759 A113760 * A113762 A113763 A113764
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KEYWORD
| base,nonn
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AUTHOR
| Giovanni Resta (g.resta(AT)iit.cnr.it), Jan 18 2006
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EXTENSIONS
| a(13)-a(26) from Robert G. Wilson v (rgwv(at)rgwv.com), Jan 19 2006
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