|
|
A002579
|
|
Number of integral points in a certain sequence of closed quadrilaterals.
(Formerly M2440 N0967)
|
|
2
|
|
|
3, 5, 8, 12, 17, 23, 30, 37, 45, 54, 64, 75, 87, 99, 112, 126, 141, 157, 174, 191, 209, 228, 248, 269, 291, 313, 336, 360, 385, 411, 438, 465, 493, 522, 552, 583, 615, 647, 680, 714, 749, 785, 822, 859, 897, 936, 976, 1017, 1059, 1101, 1144
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
REFERENCES
|
Eugene Ehrhart, 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
|
|
|
FORMULA
|
Ehrhart (1967) gives a g.f. on page 161.
G.f.: (x^5+x^4+x^3+x+1)/((1-x^6)*(1-x)^2). - Sean A. Irvine, Apr 25 2017
|
|
MATHEMATICA
|
Rest[CoefficientList[Series[(x^5 + x^4 + x^3 + x + 1) / ((1 - x^6) (1 - x)^2), {x, 0, 40}], x]] (* Vincenzo Librandi, Apr 26 2017 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|