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A100416
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Numbers n such that sum of the proper divisors of n is equal to d_1!+d_2!+...+d_k!, where d_1 d_2 ... d_k is the decimal expansion of n.
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2
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561653, 606061, 1649345, 2631227, 5657101, 25376713, 33805243, 38747603, 68760599, 77773043, 80404183, 101695597, 124781123, 125348239, 142692929, 152212087, 177464929, 184416409, 192144907, 200781041, 238715647, 241253839
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OFFSET
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1,1
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LINKS
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Table of n, a(n) for n=1..22.
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EXAMPLE
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38747603 is in the sequence because {1,769,50387} is the set of proper
divisors of 38747603 and 3!+8!+7!+4!+7!+6!+0!+3!=1+769+50387.
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MATHEMATICA
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Do[h = IntegerDigits[n]; l = Length[h]; If[DivisorSigma[1, n] - n == Sum[h[[k]]!, {k, l}], Print[n]], {n, 60000000}]
Select[Range[2413*10^5], Total[Most[Divisors[#]]]==Total[ IntegerDigits[ #]!]&] (* Harvey P. Dale, Oct 11 2018 *)
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CROSSREFS
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Cf. A101697.
Sequence in context: A250534 A234207 A124514 * A151878 A273236 A237935
Adjacent sequences: A100413 A100414 A100415 * A100417 A100418 A100419
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KEYWORD
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base,nonn
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AUTHOR
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Farideh Firoozbakht, Dec 12 2004
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EXTENSIONS
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a(9)-a(22) from Donovan Johnson, Dec 07 2008
Comment deleted by Harvey P. Dale, Oct 11 2018
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STATUS
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approved
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