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 A022146 Coordination sequence for root lattice B_4. 4
 1, 32, 224, 768, 1856, 3680, 6432, 10304, 15488, 22176, 30560, 40832, 53184, 67808, 84896, 104640, 127232, 152864, 181728, 214016, 249920, 289632, 333344, 381248, 433536, 490400, 552032, 618624, 690368 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 REFERENCES R. Bacher, P. de la Harpe and B. Venkov, Series de croissance et series d'Ehrhart associees aux reseaux de racines, C. R. Acad. Sci. Paris, 325 (Series 1) (1997), 1137-1142. LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..1000 M. Baake and U. Grimm, Coordination sequences for root lattices and related graphs, arXiv:cond-mat/9706122, Zeit. f. Kristallographie, 212 (1997), 253-256. FORMULA a(0) = 1, a(n) = 32*n^3 - 16*n^2 + 16*n. - Ralf Stephan, Sep 03 2003 G.f.: (1+28*x+102*x^2+60*x^3+x^4)/(1-x)^4 = 1+32*x*(x+1)*(2*x+1)/(1-x)^4. - Colin Barker, Apr 13 2012 MATHEMATICA CoefficientList[Series[(1+28*x+102*x^2+60*x^3+x^4)/(1-x)^4, {x, 0, 40}], x] (* Vincenzo Librandi, Apr 20 2012 *) PROG (MAGMA) [1] cat[32*n^3 - 16*n^2 + 16*n: n in [1..40]]; // Vincenzo Librandi, Apr 20 2012 CROSSREFS Sequence in context: A146089 A250232 A070053 * A160061 A269585 A199913 Adjacent sequences:  A022143 A022144 A022145 * A022147 A022148 A022149 KEYWORD nonn,easy AUTHOR mbaake(AT)sunelc3.tphys.physik.uni-tuebingen.de (Michael Baake) STATUS approved

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Last modified December 13 06:26 EST 2019. Contains 329968 sequences. (Running on oeis4.)