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A280446
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Like A065759 but where f(n) = 2*n.
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2
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5848, 6884, 58480, 68840, 394062, 584800, 688400, 3940620, 5848000, 6884000, 39406200, 58480000, 68840000
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OFFSET
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1,1
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COMMENTS
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Numbers of the form 5848*10^k, 6884*10^k, 394062*10^k, with k>=0, belong to the sequence.
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LINKS
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EXAMPLE
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5848 = concat(5*848) = concat(58*48) = concat(584*8) and (5*848 + 58*48 + 584*8) = 11696 = 2*5848.
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MAPLE
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P:=proc(q) local a, k, n; for n from 1 to q do a:=0;
for k from 1 to ilog10(n) do a:=a+(n mod 10^k)*trunc(n/10^k); od;
if a/n=2 then print(n); fi; od; end: P(10^9);
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MATHEMATICA
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Select[Range[10^6], Function[n, Module[{a = {}, e = IntegerLength@ n - 1, k}, Do[AppendTo[a, # (n - #*10^(e - k)) &@ Floor[n/10^(e - k)]], {k, 0, e - 1}]; Total@ a] == 2 n]] (* Michael De Vlieger, Jan 04 2017 *)
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CROSSREFS
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KEYWORD
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nonn,base,more
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AUTHOR
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STATUS
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approved
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