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A087645
Third column of A071223.
3
2, 6, 24, 72, 172, 352, 646, 1094, 1742, 2642, 3852, 5436, 7464, 10012, 13162, 17002, 21626, 27134, 33632, 41232, 50052, 60216, 71854, 85102, 100102, 117002, 135956, 157124, 180672, 206772, 235602, 267346, 302194, 340342, 381992, 427352, 476636
OFFSET
2,1
LINKS
Alvaro Carbonero, Beth Anne Castellano, Gary Gordon, Charles Kulick, Karie Schmitz, and Brittany Shelton, Permutations of point sets in R_d, arXiv:2106.14140 [math.CO], 2021.
T. M. Cover, The number of linearly inducible orderings of points in d-space, SIAM J. Applied Math., 15 (1967), 434-439.
FORMULA
a(n) = A052149(n+1) + 2.
a(n) = (3*n^4-10*n^3+9*n^2-2*n+24)/12. - Vladeta Jovovic, Oct 26 2003
G.f.: -2*x^2*(x^4-4*x^3+7*x^2-2*x+1) / (x-1)^5. - Colin Barker, Dec 06 2014
MATHEMATICA
CoefficientList[Series[-2 x^2*(x^4 - 4 x^3 + 7 x^2 - 2 x + 1)/(x - 1)^5, {x, 0, 38}], x][[3 ;; -1]] (* Michael De Vlieger, Oct 19 2021 *)
PROG
(PARI) Vec(-2*x^2*(x^4-4*x^3+7*x^2-2*x+1)/(x-1)^5 + O(x^100)) \\ Colin Barker, Dec 06 2014
CROSSREFS
Sequence in context: A236625 A096259 A338614 * A174700 A216158 A178847
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Oct 26 2003
EXTENSIONS
More terms from Vladeta Jovovic, Oct 26 2003
STATUS
approved