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 A090449 #19 Sep 08 2022 08:14:46 %S A090449 96,2500,27000,180075,878080,3429216,11340000,32942250,86248800, %T A090449 207352860,464199736,978193125,1956864000,3741740800,6876627840, %U A090449 12202737156,20988540000,35103820500,57249238200,91254750895,142462526976,218212500000,328451500000,486489948750 %N A090449 Fifth column (m=4) of triangle A090447. %H A090449 T. D. Noe, <a href="/A090449/b090449.txt">Table of n, a(n) for n = 4..1000</a> %H A090449 <a href="/index/Rec#order_11">Index entries for linear recurrences with constant coefficients</a>, signature (11,-55,165,-330,462,-462,330,-165,55,-11,1). %F A090449 a(n)= A090447(n, 4)= (n^4*(n-1)^3*(n-2)^2*(n-3)^1)/(1!*2!*3!*4!), n>=4. %F A090449 G.f.: -x^4*(x^6+109*x^5+1435*x^4+4735*x^3+4780*x^2+1444*x+96)/(x-1)^11. - _Colin Barker_, Jan 21 2013 %F A090449 From _Amiram Eldar_, Sep 08 2022: (Start) %F A090449 Sum_{n>=4} 1/a(n) = 700*Pi^2/9 + 4*Pi^4/15 - 40*zeta(3) - 20129/27. %F A090449 Sum_{n>=4} (-1)^n/a(n) = 30311/27 - 26*Pi^2/9 - 7*Pi^4/30 - 11008*log(2)/9 - 186*zeta(3). (End) %t A090449 LinearRecurrence[{11,-55,165,-330,462,-462,330,-165,55,-11,1},{96,2500,27000,180075,878080,3429216,11340000,32942250,86248800,207352860,464199736},40] (* _Harvey P. Dale_, Apr 10 2018 *) %Y A090449 Cf. A090447. %K A090449 nonn,easy %O A090449 4,1 %A A090449 _Wolfdieter Lang_, Dec 23 2003