This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A306210 #7 Feb 04 2019 11:22:43 %S A306210 1,1,1,1,2,1,1,2,3,1,1,3,4,4,1,1,3,8,7,5,1,1,4,10,17,11,6,1,1,4,16,26, %T A306210 31,16,7,1,1,5,19,47,56,51,22,8,1,1,5,27,65,112,106,78,29,9,1,1,6,31, %U A306210 101,176,232,183,113,37,10,1,1,6,41,131,296,407,435,295,157,46,11,1 %N A306210 T(n,k) = binomial(n + k, n) - binomial(n + floor(k/2), n) + 1, square array read by descending antidiagonals (n >= 0, k >= 0). %C A306210 There are at most T(n,k) possible values for the number of knots in an interpolatory cubature formula of degree k for an integral over an n-dimensional region. %H A306210 Ronald Cools, <a href="http://nines.cs.kuleuven.be/ecf/">Encyclopaedia of Cubature Formulas</a> %H A306210 Ronald Cools, <a href="https://doi.org/10.1007/978-94-011-2646-5_1">A Survey of Methods for Constructing Cubature Formulae</a>, In: Espelid T.O., Genz A. (eds), Numerical Integration, NATO ASI Series (Series C: Mathematical and Physical Sciences), Vol. 357, 1991, Springer, Dordrecht, pp. 1-24. %H A306210 T. N. L. Patterson, <a href="https://doi.org/10.1007/978-94-009-3889-2_27">On the Construction of a Practical Ermakov-Zolotukhin Multiple Integrator</a>, In: Keast P., Fairweather G. (eds), Numerical Integration, NATO ASI Series (Series C: Mathematical and Physical Sciences), Vol. 203, 1987, Springer, Dordrecht, pp. 269-290. %F A306210 T(n,k) = A007318(n+k,n) - A046854(n+k,n) + 1. %F A306210 G.f.: (1 - x - x^2 + x^3 - 2*y + 2*x*y + y^2 - x*y^2 + x^2*y^2)/((1 - x)*(1 - y)*(1 - x - y)*(1 - x^2 - y)). %e A306210 Square array begins: %e A306210 1, 1, 1, 1, 1, 1, 1, 1, 1, ... %e A306210 1, 2, 2, 3, 3, 4, 4, 5, 5, ... %e A306210 1, 3, 4, 8, 10, 16, 19, 27, 31, ... %e A306210 1, 4, 7, 17, 26, 47, 65, 101, 131, ... %e A306210 1, 5, 11, 31, 56, 112, 176, 296, 426, ... %e A306210 1, 6, 16, 51, 106, 232, 407, 737, 1162, ... %e A306210 1, 7, 22, 78, 183, 435, 841, 1633, 2794, ... %e A306210 1, 8, 29, 113, 295, 757, 1597, 3313, 6106, ... %e A306210 1, 9, 37, 157, 451, 1243, 2839, 6271, 12376, ... %e A306210 ... %e A306210 As triangular array, this begins: %e A306210 1; %e A306210 1, 1; %e A306210 1, 2, 1; %e A306210 1, 2, 3, 1; %e A306210 1, 3, 4, 4, 1; %e A306210 1, 3, 8, 7, 5, 1; %e A306210 1, 4, 10, 17, 11, 6, 1; %e A306210 1, 4, 16, 26, 31, 16, 7, 1; %e A306210 1, 5, 19, 47, 56, 51, 22, 8, 1; %e A306210 ... %t A306210 T[n_, k_] = Binomial[n + k, n] - Binomial[n + Floor[k/2], n] + 1; %t A306210 Table[T[k, n - k], {k, 0, n}, {n, 0, 20}] // Flatten %o A306210 (Maxima) %o A306210 T(n, k) := binomial(n + k, n) - binomial(n + floor(k/2), n) + 1$ %o A306210 create_list(T(k, n - k), n, 0, 20, k, 0, n); %Y A306210 Cf. A007318, A046854, A322596. %K A306210 nonn,easy,tabl %O A306210 0,5 %A A306210 _Franck Maminirina Ramaharo_, Jan 29 2019