OFFSET
1,2
LINKS
Robert Israel, Table of n, a(n) for n = 1..41
MathOverflow, Determinant of identity matrix plus Hilbert matrix, 2018.
FORMULA
det(I+H) = Sum_{subsets S of {1,2,...,n}} Product_{1<=i<j<=|S|} (S_i-S_j)^2 / Product_{1<= i,j <= |S|} (S_i+S_j-1).
MAPLE
f := n -> denom(LinearAlgebra:-Determinant(LinearAlgebra:-IdentityMatrix(n)+LinearAlgebra:-HilbertMatrix(n))):
map(f, [$1..30]);
MATHEMATICA
a[n_] := Det[IdentityMatrix[n] + HilbertMatrix[n]] // Denominator;
Array[a, 11] (* Jean-François Alcover, Feb 26 2018 *)
PROG
(PARI) A295427(n) = denominator( matdet( matrix(n, n, i, j, 1/(i+j-1)+(i==j)) ) ); \\ Max Alekseyev, Feb 16 2018
CROSSREFS
KEYWORD
nonn,frac
AUTHOR
Robert Israel, Feb 12 2018
STATUS
approved