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A161756
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The sum of all numbers from n up to A002808(n)-3.
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1
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1, 5, 12, 15, 18, 30, 45, 50, 55, 75, 98, 105, 112, 140, 148, 156, 164, 172, 207, 245, 255, 265, 275, 285, 330, 341, 352, 402, 455, 468, 481, 539, 553, 567, 581, 595, 660, 675, 690, 705, 720, 792, 867, 884, 901, 918, 935, 1017, 1035, 1053, 1140, 1230, 1250, 1270, 1290
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refs;
listen;
history;
text;
internal format)
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OFFSET
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1,2
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LINKS
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FORMULA
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EXAMPLE
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a(1) = 1, a(2) = 2+3, a(3) = 3+4+5.
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MATHEMATICA
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Total[Range[#[[1]], #[[2]]-3]]&/@Module[{nn=80, cm}, cm=Select[ Range[ nn], CompositeQ]; Thread[{Range[Length[cm]], cm}]] (* Harvey P. Dale, Nov 04 2019 *)
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CROSSREFS
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KEYWORD
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nonn,less
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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