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 A298424 Matula-Goebel numbers of rooted trees in which all positive outdegrees are the same. 7
 1, 2, 3, 4, 5, 8, 11, 14, 16, 31, 32, 49, 64, 76, 86, 127, 128, 256, 301, 424, 454, 512, 709, 722, 886, 1024, 1532, 1589, 1849, 2048, 2096, 3101, 3986, 4096, 5381, 6418, 6859, 8192, 9761, 9952, 11236, 13766, 13951, 14554, 16384, 19049, 21884, 22463, 23512 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS EXAMPLE Sequence of trees begins: 1   o 2   (o) 3   ((o)) 4   (oo) 5   (((o))) 8   (ooo) 11  ((((o)))) 14  (o(oo)) 16  (oooo) 31  (((((o))))) 32  (ooooo) 49  ((oo)(oo)) 64  (oooooo) 76  (oo(ooo)) 86  (o(o(oo))) 127 ((((((o)))))) 128 (ooooooo) 256 (oooooooo) 301 ((oo)(o(oo))) 424 (ooo(oooo)) 454 (o((oo)(oo))) 512 (ooooooooo) 709 (((((((o))))))) 722 (o(ooo)(ooo)) 886 (o(o(o(oo)))) MATHEMATICA MGtree[n_]:=If[n===1, {}, MGtree/@Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]]; soQ[n_]:=Or[n===1, SameQ@@Length/@Cases[MGtree[n], {__}, {0, Infinity}]]; Select[Range[1000], soQ] CROSSREFS Cf. A000081, A000598, A001190, A003238, A007097, A111299, A214577, A276625, A298422, A298423, A298426. Sequence in context: A281493 A181341 A174181 * A008812 A144679 A207890 Adjacent sequences:  A298421 A298422 A298423 * A298425 A298426 A298427 KEYWORD nonn AUTHOR Gus Wiseman, Jan 19 2018 STATUS approved

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Last modified February 22 09:43 EST 2019. Contains 320390 sequences. (Running on oeis4.)