A162442 Denominators of the column sums of the EG1 matrix coefficients.

2, 16, 48, 512, 1280, 2048, 14336, 262144, 589824, 2621440, 5767168, 50331648, 109051904, 469762048, 67108864, 34359738368, 73014444032, 103079215104, 652835028992, 1099511627776, 3848290697216, 48378511622144

Offset: 2

Author

Johannes W. Meijer, Jul 06 2009

Keywords

• easy
• frac
• nonn

Comments

For the definition of the EG1 matrix coefficients see A162440.

We define the columns sums by cs(n) = sum(EG1[2*m-1,n], m = 1.. infinity) for n => 2.

Crossrefs

Equals A052469(n-1)/2 for n=>2.

cs(n) = (1/(n-1))*A001803(n-1)/A046161(n-1) for n=>2.

Cf. A162440 and A162441.

Formula

a(n) = denom(cs(n)) and numer(cs(n)) = A162441(n) with cs(n) = (2^(2-2*n)/(n-1))*((2*n-1)!/((n-1)!^2)).

a(n) = denom((1/(n-1))*(2*n-1)*binomial(2*n-2,n-1)/4^(n-1))