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A157716
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One-eighth of triangular numbers (integers only).
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1
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0, 15, 17, 62, 66, 141, 147, 252, 260, 395, 405, 570, 582, 777, 791, 1016, 1032, 1287, 1305, 1590, 1610, 1925, 1947, 2292, 2316, 2691, 2717, 3122, 3150, 3585, 3615, 4080, 4112, 4607, 4641, 5166, 5202, 5757, 5795, 6380, 6420, 7035, 7077, 7722, 7766, 8441
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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FORMULA
| G.f.: x^2*(15+2*x+15*x^2)/((1+x)^2*(1-x)^3 ). [From Maksym Voznyy (voznyy(AT)mail.ru), Jul 26 2009]
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MATHEMATICA
| lst={}; s=0; Do[s+=n/8; If[Floor[s]==s, AppendTo[lst, s]], {n, 0, 7!}]; lst
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CROSSREFS
| Cf. A000217, A101877.
Sequence in context: A124334 A002155 A091017 * A113968 A093812 A159840
Adjacent sequences: A157713 A157714 A157715 * A157717 A157718 A157719
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KEYWORD
| nonn
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AUTHOR
| Vladimir Orlovsky (4vladimir(AT)gmail.com), Mar 04 2009
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EXTENSIONS
| G.f. proposed by Maksym Voznyy checked and corrected by R. J. Mathar, Sep 16 2009.
Definition edited by N. J. A. Sloane, Mar 08 2009
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