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 A002578 Number of integral points in a certain sequence of open quadrilaterals. (Formerly M2529 N0997) 2
 0, 0, 1, 3, 6, 9, 13, 18, 24, 31, 39, 47, 56, 66, 77, 89, 102, 115, 129, 144, 160, 177, 195, 213, 232, 252, 273, 295, 318, 341, 365, 390, 416, 443, 471, 499, 528, 558, 589, 621, 654, 687, 721, 756, 792, 829, 867, 905, 944, 984, 1025, 1067, 1110 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 REFERENCES Ehrhart, Eugene; Deux corollaires de la loi de réciprocité du polyèdre rationnel. C. R. Acad. Sci. Paris Ser. A-B 265 1967 A160-A162. N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 E. Ehrhart, Deux corollaires de la loi de réciprocité du polyèdre rationnel, C. R. Acad. Sci. Paris Ser. A-B 265 1967 A160-A162. [Annotated scanned copy] FORMULA Ehrhart (1967) gives a g.f. on page 161. G.f.: x^3*(x^5+x^4+x^2+x+1)/((1-x^6)*(1-x)^2). - Sean A. Irvine, Apr 25 2017 MATHEMATICA CoefficientList[Series[x^2 (1 + x + x^2 + x^4 + x^5) / ((1 - x^6) (1 - x)^2), {x, 0, 40}], x] (* Vincenzo Librandi, Apr 26 2017 *) CROSSREFS Cf. A002579. Sequence in context: A132352 A033436 A059293 * A129728 A310160 A117469 Adjacent sequences:  A002575 A002576 A002577 * A002579 A002580 A002581 KEYWORD nonn,easy AUTHOR EXTENSIONS More terms from Sean A. Irvine, Apr 25 2017 STATUS approved

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Last modified December 11 20:17 EST 2018. Contains 318051 sequences. (Running on oeis4.)