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 A032028 Number of rooted planar trees (n+1 nodes) where any 2 subtrees extending from same node are different. 1
 1, 1, 1, 2, 4, 9, 23, 62, 167, 461, 1309, 3784, 11018, 32431, 96294, 288246, 868107, 2629499, 8005166, 24482202, 75177313, 231697259, 716488213, 2222381516, 6912569477, 21556270329, 67380727837, 211080434346 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 LINKS Andrew Howroyd, Table of n, a(n) for n = 1..200 C. G. Bower, Transforms (2) FORMULA "CGK" (necklace, elements, unlabeled) transform of A032027 (shifted right one place). PROG (PARI) AGK(v)={apply(p->subst(serlaplace(y^0*p), y, 1), Vec(prod(k=1, #v, (1 + x^k*y + O(x*x^#v))^v[k])-1, -#v))} CGK(v)={apply(p->subst(serlaplace(p/y), y, 1), Vec(prod(k=1, #v, (1 + x^k*y + O(x*x^#v))^v[k])-1, -#v))} seq(n)={my(v=[1]); for(i=3, n, v=concat([1], AGK(v))); concat([1], CGK(v))} \\ Andrew Howroyd, Sep 20 2018 CROSSREFS Sequence in context: A027133 A213683 A032010 * A190277 A274882 A127384 Adjacent sequences:  A032025 A032026 A032027 * A032029 A032030 A032031 KEYWORD nonn AUTHOR STATUS approved

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Last modified November 13 19:25 EST 2018. Contains 317149 sequences. (Running on oeis4.)