A098612 Sum of all matrix elements M(i,j) = (i^2)/(i+j) multiplied by (2*n)!/n!.

0, 1, 38, 1172, 37080, 1265640, 47157936, 1918916160, 84991075200, 4079108462400, 211158556963200, 11737075895677440, 697609321424870400, 44168292113326617600, 2968571902157455104000, 211131415096140736512000

Offset

0,3

Links

Table of n, a(n) for n=0..15.

Formula

a(n) = (2*n)!/n!*Sum[Sum[(i^2)/(i+j), {i, 1, n}], {j, 1, n}]

Mathematica

Table[(2*n)!/n!*Sum[Sum[(i^2)/(i+j), {i, 1, n}], {j, 1, n}], {n, 0, 15}]

Crossrefs

Sequence in context: A285236 A208949 A255496 * A268739 A239043 A137030

Adjacent sequences: A098609 A098610 A098611 * A098613 A098614 A098615

Keyword

nonn

Author

Alexander Adamchuk, Oct 26 2004

Status

approved