%I #36 Sep 08 2022 08:46:12
%S 1,6,22,63,154,336,672,1254,2211,3718,6006,9373,14196,20944,30192,
%T 42636,59109,80598,108262,143451,187726,242880,310960,394290,495495,
%U 617526,763686,937657,1143528,1385824,1669536,2000152,2383689,2826726,3336438,3920631,4587778,5347056,6208384,7182462
%N a(n) = n*(n+1)*(n+2)*(n+3)*(n^2+3*n+26)/720.
%C Antidiagonal sums of the array of 4-dimensional solid numbers shown in Table 3 of Sardelis and Valahas paper (see also Example field).
%C See A257199 (second comment) for the general formula of this type of numbers: the sequence correspond to the case j = 4.
%C Binomial transform of (1, 5, 11, 14, 11, 5, 1, 0, 0, 0, ...). - _Gary W. Adamson_, Aug 26 2015
%H D. A. Sardelis and T. M. Valahas, <a href="http://arxiv.org/abs/0805.4070">On Multidimensional Pythagorean Numbers</a>, arXiv:0805.4070 [math.GM], 2008.
%H <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (7,-21,35,-35,21,-7,1).
%F G.f.: x*(-1 + x - x^2)/(-1 + x)^7.
%e Array in Comments begins:
%e 1, 5, 15, 35, 70, 126, 210, 330, ...
%e 1, 6, 20, 50, 105, 196, 336, 540, ...
%e 1, 7, 25, 65, 140, 266, 462, 750, ...
%e 1, 8, 30, 80, 175, 336, 588, 960, ...
%e 1, 9, 35, 95, 210, 406, 714, 1170, ...
%e 1, 10, 40, 110, 245, 476, 840, 1380, ...
%t Table[n (n + 1) (n + 2) (n + 3) (n^2 + 3n + 26)/720, {n, 40}]
%o (Magma) [n*(n+1)*(n+2)*(n+3)*(n^2+3*n+26)/720: n in [1..40]]; // _Vincenzo Librandi_, Apr 18 2015
%o (PARI) first(m)=vector(m,i,i*(i+1)*(i+2)*(i+3)*(i^2+3*i+26)/720) \\ _Anders Hellström_, Aug 26 2015
%o (PARI) Vec(x*(-1 + x - x^2)/(-1 + x)^7 + O(x^40)) \\ _Michel Marcus_, Aug 27 2015
%Y Cf. A257199, A257201.
%Y See A080852 for another version of the array.
%K nonn,easy
%O 1,2
%A _Luciano Ancora_, Apr 18 2015