Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
A001849
Crystal ball sequence for 7-dimensional cubic lattice.
(Formerly M4979 N2139)
9
1, 15, 113, 575, 2241, 7183, 19825, 48639, 108545, 224143, 433905, 795455, 1392065, 2340495, 3800305, 5984767, 9173505, 13726991, 20103025, 28875327, 40754369, 56610575, 77500017, 104692735, 139703809, 184327311, 240673265, 311207743, 398796225, 506750351
OFFSET
0,2
COMMENTS
This is row/column 7 of the Delannoy numbers array, A008288, which is the main entry for these numbers, listing many more properties. - Shel Kaphan, Jan 06 2023
REFERENCES
L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 81.
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
J. H. Conway and N. J. A. Sloane, Low-Dimensional Lattices VII: Coordination Sequences, Proc. Royal Soc. London, A453 (1997), 2369-2389 (pdf).
Simon Plouffe, Approximations de séries génératrices et quelques conjectures, Dissertation, Université du Québec à Montréal, 1992; arXiv:0911.4975 [math.NT], 2009.
Simon Plouffe, 1031 Generating Functions, Appendix to Thesis, Montreal, 1992.
R. G. Stanton and D. D. Cowan, Note on a "square" functional equation, SIAM Rev., 12 (1970), 277-279.
FORMULA
G.f.: (1+x)^7 /(1-x)^8.
a(n) = (8*n^7 + 28*n^6 + 224*n^5 + 490*n^4 + 1232*n^3 + 1372*n^2 + 1056*n + 315)/315. - Johannes W. Meijer, Jul 14 2013
Sum_{n >= 1} (-1)^(n+1)/(n*a(n-1)*a(n)) = 319/420 - log(2) = (1 - 1/2 + 1/3 - 1/4 + 1/5 - 1/6 + 1/7) - log(2). - Peter Bala, Mar 23 2024
MAPLE
A001849:=(z+1)**7/(z-1)**8; # conjectured by Simon Plouffe in his 1992 dissertation
MATHEMATICA
CoefficientList[Series[(z + 1)^7/(z - 1)^8, {z, 0, 200}], z] (* Vladimir Joseph Stephan Orlovsky, Jun 19 2011 *)
CROSSREFS
Cf. A240876.
Row/column 7 of A008288.
Sequence in context: A295384 A110822 A222410 * A115150 A115138 A233326
KEYWORD
nonn,easy
STATUS
approved