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 A032306 Number of rooted trees with leaves of 2 colors where any 2 subtrees extending from the same node have a different number of nodes. 1
 2, 2, 2, 6, 10, 26, 66, 174, 442, 1202, 3298, 9166, 25674, 72810, 206826, 595150, 1712634, 4978458, 14494130, 42502030, 124660402, 368221002, 1087321354, 3229266742, 9591013738, 28624735962, 85404444970 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Andrew Howroyd, Table of n, a(n) for n = 1..500 FORMULA Shifts left under "EFK" (unordered, size, unlabeled) transform. PROG (PARI) EFK(p, n)={prod(k=1, n, 1 + polcoef(p, k)*x^k + O(x*x^n))} seq(n)={my(p=O(1)); for(i=1, n, p=1+EFK(x*p, i-1)); Vec(p)} \\ Andrew Howroyd, Sep 20 2018 CROSSREFS Sequence in context: A052537 A024945 A186507 * A227847 A058756 A237614 Adjacent sequences:  A032303 A032304 A032305 * A032307 A032308 A032309 KEYWORD nonn AUTHOR STATUS approved

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Last modified January 18 07:18 EST 2019. Contains 319269 sequences. (Running on oeis4.)