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The sixth moments of the alternated squared binomial coefficients; a(n) = Sum_{m=0..n} (-1)^m*m^6*binomial(n, m)^2.
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%I #31 Sep 08 2022 08:46:24

%S 0,-1,60,-162,-5280,20250,128520,-569380,-1854720,9338490,20097000,

%T -113704668,-181621440,1142905764,1447926480,-10042461000,

%U -10529925120,79859881530,71384175720,-587933314540,-457825368000,4070529226764

%N The sixth moments of the alternated squared binomial coefficients; a(n) = Sum_{m=0..n} (-1)^m*m^6*binomial(n, m)^2.

%D H. W. Gould, Combinatorial Identities, 1972.

%H Seiichi Manyama, <a href="/A329521/b329521.txt">Table of n, a(n) for n = 0..1000</a>

%F a(n) = (-1)^((n+2)/2)*binomial(n, n/2)*(n^3*(n+1)*(3n-1)/4), if n is even,

%F a(n) = (-1)^((n-1)/2)*binomial(n,((n+1)/2))*(n^2*( n+1)*(n^3+n^2-9n+3)/8), if n is odd.

%F G.f.: x*(-1 + 60*x - 188*x^2 - 3720*x^3 + 15752*x^4 + 8400*x^5 - 90928*x^6 + 79680*x^7 + 42112*x^8 - 69120*x^9 + 17408*x^10)/(1+4*x^2)^(13/2). - _Stefano Spezia_, Nov 15 2019

%t Table[Sum[(-1)^m*m^6*(Binomial[n, m])^2, {m, 0, n}], {n, 21}]

%o (Magma) [&+[(-1)^m*m^6*(Binomial(n,m))^2:m in [0..n]]:n in [0..21]]; // _Marius A. Burtea_, Nov 15 2019

%o (PARI) a(n) = sum(m=0, n, (-1)^m*m^6*binomial(n , m)^2); \\ _Michel Marcus_, Nov 15 2019

%Y Cf. A074334, A294486, A329444.

%K sign

%O 0,3

%A _Nikita D. Gogin_, Nov 15 2019