Denominator of 2n/v(n)^2, where v(1) = 0, v(2) = 1, and v(n) = v(n-1)/(n-2) + v(n-2) for n >= 3. (Limit of 2n/v(n)^2 is Pi.)

A239225

Denominator of 2n/v(n)^2, where v(1) = 0, v(2) = 1, and v(n) = v(n-1)/(n-2) + v(n-2) for n >= 3. (Limit of 2n/v(n)^2 is Pi.)

Terms

    a(0) =1a(1) =1a(2) =1a(3) =9a(4) =9a(5) =75a(6) =225a(7) =1225a(8) =1225a(9) =19845a(10) =99225a(11) =160083a(12) =480249a(13) =1288287a(14) =3006003a(15) =41409225a(16) =41409225a(17) =1329696225a(18) =11967266025a(19) =10667118605a(20) =53335593025a(21) =85530896451a(22) =940839860961

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