cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A303026 Matula-Goebel numbers of series-reduced anti-binary (no unary or binary branchings) rooted trees.

Original entry on oeis.org

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

Views

Author

Gus Wiseman, Aug 15 2018

Keywords

Examples

			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)
		

Crossrefs

Programs

  • Mathematica
    azQ[n_]:=Or[n==1,And[PrimeOmega[n]>2,And@@Cases[FactorInteger[n],{p_,_}:>azQ[PrimePi[p]]]]]
    Select[Range[1000],azQ]