A131786 Repeated terms in A131771; a(n) = A131770( (n+1)*(n+2)/2 - 1 ) for n>=0.

1, 4, 20, 104, 592, 3592, 23212, 158652, 1141964, 8621820, 68063300, 560324488, 4799515756, 42690098440, 393605305676, 3755794383536, 37034899306132, 376877989985712, 3953002335087184, 42686126230197500, 474037727935110620