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A141091
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Integral quotients of products of consecutive composites divided by their sums: sums (divisors).
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6
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4, 27, 63, 112, 175, 224, 250, 400, 847, 896, 2368, 2448, 2695, 3596, 4300, 4624, 4961, 5076, 5546, 6032, 6156, 6664, 8750, 9048, 9200, 9976, 10295, 11620, 12312, 13572, 14697, 15872, 16275, 18139, 18352, 23572, 24304, 25544, 26814, 27072, 29986
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OFFSET
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1,1
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LINKS
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FORMULA
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Find the products and sums of consecutive composites. When the products divided by the sums produce integral quotients, add terms to sequence.
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EXAMPLE
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a(3) = 63 because 4*6*8*9*10*12*14 = 2903040 and 4+6+8+9+10+12+14 = 63; 2903040/63 = 46080, integral -- 63 is added to the sequence.
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MATHEMATICA
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comp = Select[Range[500], CompositeQ]; sum = Accumulate[comp]; sum[[Position[ Rest@FoldList[Times, 1, comp]/sum, _?IntegerQ] // Flatten]] (* Amiram Eldar, Jan 12 2020 *)
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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