A032118 Shifts left 2 places under "BIJ" (reversible, indistinct, labeled) transform.

1, 1, 1, 2, 7, 39, 282, 2476, 25468, 300104, 3984742, 58857048, 957156654, 16992957454, 327018332848, 6780662275976, 150700528101856, 3573879622264536, 90079771978313256, 2404666535666287000, 67774524657985373248, 2011157217480732750512, 62675350084052135287072

Offset

1,4

Links

Andrew Howroyd, Table of n, a(n) for n = 1..200

C. G. Bower, Transforms (2)

Prog

(PARI) BIJ(p)={(1-p^2/2)/(1-p) - 1}
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

Crossrefs

Sequence in context: A330470 A364336 A266310 * A369087 A125660 A112944

Adjacent sequences: A032115 A032116 A032117 * A032119 A032120 A032121

Keyword

nonn,eigen

Author

Christian G. Bower

Extensions

Terms a(21) and beyond from Andrew Howroyd, Sep 19 2018

Status

approved