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A053742
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Sum of odd numbers in range 10*n to 10*n+9.
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16
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25, 75, 125, 175, 225, 275, 325, 375, 425, 475, 525, 575, 625, 675, 725, 775, 825, 875, 925, 975, 1025, 1075, 1125, 1175, 1225, 1275, 1325, 1375, 1425, 1475, 1525, 1575, 1625, 1675, 1725, 1775, 1825, 1875, 1925, 1975, 2025, 2075, 2125, 2175, 2225, 2275
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OFFSET
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0,1
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COMMENTS
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Integers that are the product of two integers ending with 5. - Michel Marcus, Mar 16 2019
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LINKS
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FORMULA
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a(n) = 25 + 50*n.
a(n) = 2*a(n-1) - a(n-2).
G.f.: 25*(1+x)/(1-x)^2. (End)
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EXAMPLE
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25 = 1+3+5+7+9; 75 = 11+13+15+17+19; ...
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MAPLE
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MATHEMATICA
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Range[25, 2275, 50] (* or *) NestList[#+50&, 25, 50] (* Harvey P. Dale, Aug 11 2011 *)
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PROG
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(Sage) [25*(2*n+1) for n in (0..50)] # G. C. Greubel, Sep 06 2019
(GAP) List([0..50], n-> 25*(2*n+1)); # G. C. Greubel, Sep 06 2019
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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