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A303026
Matula-Goebel numbers of series-reduced anti-binary (no unary or binary branchings) rooted trees.
5
1, 8, 16, 32, 64, 76, 128, 152, 212, 256, 304, 424, 512, 524, 608, 722, 848, 1024, 1048, 1216, 1244, 1444, 1532, 1696, 2014, 2048, 2096, 2432, 2488, 2876, 2888, 3064, 3392, 3524, 4028, 4096, 4192, 4864, 4976, 4978, 5204, 5618, 5752, 5776, 6128, 6476, 6784
OFFSET
1,2
EXAMPLE
The sequence of series-reduced anti-binary rooted trees together with their Matula-Goebel numbers begins:
1: o
8: (ooo)
16: (oooo)
32: (ooooo)
64: (oooooo)
76: (oo(ooo))
128: (ooooooo)
152: (ooo(ooo))
212: (oo(oooo))
256: (oooooooo)
304: (oooo(ooo))
424: (ooo(oooo))
512: (ooooooooo)
524: (oo(ooooo))
608: (ooooo(ooo))
722: (o(ooo)(ooo))
848: (oooo(oooo))
1024: (oooooooooo)
1048: (ooo(ooooo))
1216: (oooooo(ooo))
1244: (oo(oooooo))
1444: (oo(ooo)(ooo))
1532: (oo(oo(ooo)))
1696: (ooooo(oooo))
2014: (o(ooo)(oooo))
2048: (ooooooooooo)
MATHEMATICA
azQ[n_]:=Or[n==1, And[PrimeOmega[n]>2, And@@Cases[FactorInteger[n], {p_, _}:>azQ[PrimePi[p]]]]]
Select[Range[1000], azQ]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Aug 15 2018
STATUS
approved