(x,y) = (a(n),a(n+1)) are the solutions of (t(x)+t(y))/(1+xy) = t(4) = 10, where t(n) denotes the n-th triangular number t(n) = n*(n+1)/2.

A065930

(x,y) = (a(n),a(n+1)) are the solutions of (t(x)+t(y))/(1+xy) = t(4) = 10, where t(n) denotes the n-th triangular number t(n) = n*(n+1)/2.

Terms

    a(0) =4a(1) =79a(2) =1575a(3) =31420a(4) =626824a(5) =12505059a(6) =249474355a(7) =4976982040a(8) =99290166444

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