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%I #9 Sep 20 2018 00:32:20
%S 1,1,1,2,7,39,282,2476,25468,300104,3984742,58857048,957156654,
%T 16992957454,327018332848,6780662275976,150700528101856,
%U 3573879622264536,90079771978313256,2404666535666287000,67774524657985373248,2011157217480732750512,62675350084052135287072
%N Shifts left 2 places under "BIJ" (reversible, indistinct, labeled) transform.
%H Andrew Howroyd, <a href="/A032118/b032118.txt">Table of n, a(n) for n = 1..200</a>
%H C. G. Bower, <a href="/transforms2.html">Transforms (2)</a>
%o (PARI) BIJ(p)={(1-p^2/2)/(1-p) - 1}
%o seq(n)={my(p=x+O(x*x^(n%2))); for(i=1, n\2, p=intformal(1 + intformal(1 + BIJ(p)))); Vec(serlaplace(p))} \\ _Andrew Howroyd_, Sep 19 2018
%K nonn,eigen
%O 1,4
%A _Christian G. Bower_
%E Terms a(21) and beyond from _Andrew Howroyd_, Sep 19 2018