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 A098606 Sum of all matrix elements M(i,j) = (i^2)/(i+j). 0
 0, 1, 76, 7032, 889920, 151876800, 33953713920, 9671337446400, 3426840152064000, 1480226878835712000, 766252171508060160000, 468506511112577236992000, 334155981137427201392640000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS FORMULA a(n) = (2*n)!*Sum[Sum[(i^2)/(i+j), {i, 1, n}], {j, 1, n}] MATHEMATICA Table[(2*n)!*Sum[Sum[(i^2)/(i+j), {i, 1, n}], {j, 1, n}], {n, 0, 15}] CROSSREFS Sequence in context: A198476 A234778 A139671 * A093276 A184290 A093238 Adjacent sequences:  A098603 A098604 A098605 * A098607 A098608 A098609 KEYWORD nonn AUTHOR Alexander Adamchuk, Oct 26 2004 STATUS approved

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Last modified December 8 06:49 EST 2021. Contains 349590 sequences. (Running on oeis4.)