Search: id:A046127 Results 1-1 of 1 results found. %I A046127 %S A046127 0,2,4,8,16,30,52,84,128,186,260,352,464,598,756,940,1152,1394,1668, %T A046127 1976,2320,2702,3124,3588,4096,4650,5252,5904,6608,7366,8180,9052, %U A046127 9984,10978,12036,13160,14352,15614,16948,18356,19840,21402,23044 %N A046127 Maximal number of regions into which space can be divided by n spheres. %C A046127 If Y is a 2-subset of an n-set X then, for n>=2, a(n-2) is equal to the number of 2-subsets and 4-subsets of X having exactly one element in common with Y. - Milan R. Janjic (agnus(AT)blic.net), Dec 28 2007 %D A046127 L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 73, Problem 4. %D A046127 A. M. Yaglom and I. M. Yaglom: Challenging Mathematical Problems with Elementary Solutions. Vol. I. Combinatorial Analysis and Probability Theory. New York: Dover Publications, Inc., 1987, p. 13, #45 (First published: San Francisco: Holden-Day, Inc., 1964) %H A046127 T. D. Noe, Table of n, a(n) for n=0..1000 %H A046127 Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics. %F A046127 a(n)=n(n^2-3n+8)/3 (n>0). %F A046127 n hyperspheres divide R^k into at most C(n-1, k) + Sum_{i=0..k} C(n, i) regions. %Y A046127 Cf. A014206 (dim 2), A046127 (dim 3), A059173 (dim 4), A059174 (dim 5). See also A000124, A000125. A row of A059250. %Y A046127 Sequence in context: A054154 A018469 A098904 this_sequence A075529 A005305 A125548 %Y A046127 Adjacent sequences: A046124 A046125 A046126 this_sequence A046128 A046129 A046130 %K A046127 nonn,easy,nice %O A046127 0,2 %A A046127 Eric Weisstein (eric(AT)weisstein.com) Search completed in 0.001 seconds