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A360372
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Numbers k >= 1 such that k divides Sum_{i=1..k} A007088(i).
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0
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1, 11, 21, 23, 37, 461, 94101, 14958901, 16364133, 134375017, 192594821, 416095237, 4074380993, 82482257999
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OFFSET
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1,2
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COMMENTS
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The arithmetic mean of the first k binary numbers, taken as decimal numbers, is an integer.
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LINKS
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EXAMPLE
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k = 11: (1 + 10 + 11 + 100 + 101 + 110 + 111 + 1000 + 1001 + 1010 + 1011) / 11 = 406, thus 11 is a term.
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MATHEMATICA
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s = 0; seq = {}; Do[s += FromDigits[IntegerDigits[k, 2]]; If[Divisible[s, k], AppendTo[seq, k]], {k, 1, 1000}]; seq (* Amiram Eldar, Feb 04 2023 *)
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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