(x,y) = (a(n),a(n+1)) are the solutions of (t(x)+t(y))/(1+xy) = t(2) = 3, where t(n) denotes the n-th triangular number t(n) = n(n+1)/2.

A065928

(x,y) = (a(n),a(n+1)) are the solutions of (t(x)+t(y))/(1+xy) = t(2) = 3, where t(n) denotes the n-th triangular number t(n) = n(n+1)/2.

Terms

    a(0) =2a(1) =11a(2) =63a(3) =366a(4) =2132a(5) =12425a(6) =72417a(7) =422076a(8) =2460038a(9) =14338151a(10) =83568867a(11) =487075050a(12) =2838881432a(13) =16546213541a(14) =96438399813a(15) =562084185336

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