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 A298479 Matula-Goebel numbers of rooted trees in which all positive outdegrees are different. 2
 1, 2, 4, 6, 7, 8, 12, 16, 19, 24, 28, 32, 38, 42, 48, 52, 53, 56, 57, 64, 68, 74, 84, 96, 104, 106, 107, 112, 128, 131, 134, 136, 152, 159, 163, 168, 178, 192, 208, 212, 224, 228, 256, 262, 263, 272, 296, 304, 311, 318, 336, 356, 384, 393, 416, 446, 448, 456 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS EXAMPLE Sequence of trees begins: 1 o 2 (o) 4 (oo) 6 (o(o)) 7 ((oo)) 8 (ooo) 12 (oo(o)) 16 (oooo) 19 ((ooo)) 24 (ooo(o)) 28 (oo(oo)) 32 (ooooo) 38 (o(ooo)) 42 (o(o)(oo)) 48 (oooo(o)) 52 (oo(o(o))) 53 ((oooo)) 56 (ooo(oo)) 57 ((o)(ooo)) 64 (oooooo) 68 (oo((oo))) 74 (o(oo(o))) 84 (oo(o)(oo)) 96 (ooooo(o)) MATHEMATICA MGtree[n_]:=If[n===1, {}, MGtree/@Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]]; doQ[n_]:=Or[n===1, UnsameQ@@Length/@Cases[MGtree[n], {__}, {0, Infinity}]]; Select[Range[1000], doQ] CROSSREFS Cf. A000081, A001221, A004111, A007097, A032305, A061775, A111299, A276625, A290760, A297571, A298120, A298422, A298424, A298478. Sequence in context: A352089 A358458 A014855 * A015924 A096750 A088458 Adjacent sequences: A298476 A298477 A298478 * A298480 A298481 A298482 KEYWORD nonn AUTHOR Gus Wiseman, Jan 19 2018 STATUS approved

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Last modified March 20 21:07 EDT 2023. Contains 361391 sequences. (Running on oeis4.)