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A032010
Number of rooted planar trees where any 2 subtrees extending from same node have a different number of nodes.
1
1, 1, 1, 2, 4, 9, 23, 62, 164, 449, 1263, 3636, 10500, 30859, 90895, 271178, 810918, 2447715, 7406439, 22589066, 68974940, 211989119, 652180385, 2016872920, 6242930834, 19412141273, 60390977831, 188627507266
OFFSET
1,4
FORMULA
"CFK" (Necklace, size, unlabeled) transform of A032009 (shifted right one place)
PROG
(PARI)
AFK(v)={apply(p->subst(serlaplace(y^0*p), y, 1), Vec(-1+prod(k=1, #v, 1 + v[k]*x^k*y + O(x*x^#v)), -#v))}
CFK(v)={apply(p->subst(serlaplace(p/y), y, 1), Vec(-1+prod(k=1, #v, 1 + v[k]*x^k*y + O(x*x^#v)), -#v))}
seq(n)={my(v=[1]); for(i=3, n, v=concat([1], AFK(v))); concat([1], CFK(v))} \\ Andrew Howroyd, Sep 20 2018
CROSSREFS
Sequence in context: A027133 A339296 A213683 * A032028 A190277 A274882
KEYWORD
nonn
STATUS
approved