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A049981
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a(n) is the number of arithmetic progressions of positive integers, strictly increasing with sum <= n.
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15
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1, 2, 4, 6, 9, 13, 17, 21, 28, 34, 40, 49, 56, 64, 77, 86, 95, 110, 120, 132, 150, 163, 175, 195, 210, 225, 248, 265, 280, 308, 324, 342, 370, 390, 412, 445, 464, 486, 519, 545, 566, 605, 627, 653, 696, 723, 747, 790, 817, 850, 894, 925, 952, 1002, 1036, 1070, 1119, 1153, 1183, 1243, 1274, 1310
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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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G.f.: (g.f. of A049980)/(1-x). (End)
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CROSSREFS
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Cf. A014405, A014406, A049980, A049982, A049983, A049986, A049987, A068322, A068323, A068324, A127938, A175342.
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KEYWORD
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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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