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A106364
Mobiles (cycle rooted trees) where no branch is identical to its adjacent neighbor.
1
1, 1, 1, 2, 3, 6, 14, 30, 68, 159, 381, 914, 2238, 5508, 13701, 34288, 86401, 218818, 557067, 1424083, 3655221, 9414642, 24328133, 63049458, 163844470, 426831429, 1114496370, 2916228670, 7645777113, 20082543578, 52839735409, 139251228967
OFFSET
1,4
FORMULA
Shifts left under CycleBG transform.
CycleBG transform T(A) = invMOEBIUS(invEULER(Carlitz(A)) + A(x^2) - A) + A.
Carlitz transform T(A(x)) has g.f. 1/(1-sum(k>0, (-1)^(k+1)*A(x^k))).
General formula for the CycleBG transform: T(A)(x) = A(x) - Sum_{k>=0} A(x^{2k+1}) + Sum_{k>=1} (phi(k)/k)*log(Carlitz(A)(x^k)). For a proof, see the links in the documentation of sequence A106368. - Petros Hadjicostas, Oct 08 2017
CROSSREFS
Cf. A032200.
Sequence in context: A250022 A240749 A331684 * A211931 A264078 A006444
KEYWORD
nonn,eigen
AUTHOR
Christian G. Bower, Apr 29 2005
STATUS
approved