A108532 Number of asymmetric mobiles (cycle rooted trees) with n nodes and 2-colored internal (non-leaf) nodes.

1, 2, 4, 12, 38, 136, 490, 1852, 7108, 27880, 110892, 447060, 1821252, 7489732, 31045350, 129587996, 544228664, 2298008824, 9750218012, 41548438040, 177740526076, 763046178960, 3286318131646, 14195239150556, 61481540391722

Offset: 1

Author

Christian G. Bower, Jun 07 2005

Keywords

• nonn
• eigen

Links

• Andrew Howroyd, Table of n, a(n) for n = 1..200
• Index entries for sequences related to mobiles
• C. G. Bower, Transforms (2)

Crossrefs

Cf. A032171, A108530, A108531.

Programs

PARI

CHK(p,n)={sum(d=1, n, moebius(d)/d*log(subst(1/(1+O(x*x^(n\d))-p), x, x^d)))}
seq(n)={my(p=O(1));for(i=1, n, p=1+2*CHK(x*p, i)); Vec(p)} \\ Andrew Howroyd, Jun 20 2018

Formula

Shifts left and halves under CHK transform.