1 / 3, - 2 / 15, 3 / 35, - 4 / 63 | Math enthusiast | Mathematical art

1 / 3, - 2 / 15, 3 / 35, - 4 / 63

Molecules 1,2,3,4
Denominator 1 × 3,3 × 5,5 × 7,7 × 9
Symbol + - + - + -
So the nth is the nth power of (- 1) × n / [(2n-1) (2n + 1)]

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