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.

A253644 Numbers n such that n^k is zeroless for k=0,...,5.

Original entry on oeis.org

1, 2, 3, 5, 6, 13, 14, 17, 23, 24, 26, 31, 58, 62, 66, 68, 72, 76, 88, 96, 137, 168, 188, 233, 244, 262, 264, 296, 337, 376, 382, 383, 483, 488, 511, 514, 518, 519, 582, 628, 719, 736, 786, 816, 822, 928, 938, 971, 978, 1122, 1178, 1291, 1331, 1392, 1413, 1414, 1663, 1777
Offset: 1

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Author

M. F. Hasler, Jan 07 2015

Keywords

Comments

A subsequence of A252484 (analog for k <= 4) which contains A253647 (analog including k = 6) as a subsequence. Primes in this sequence are listed in A253645.
Conjectured to be finite.

Crossrefs

Programs

  • Maple
    filter:= proc(x)
      local k;
      for k from 1 to 5 do
        if has(convert(x^k,base,10),0) then return false fi
      od:
      true
    end proc:
    select(filter, [$1..10000]); # Robert Israel, Jan 07 2015
  • Mathematica
    Select[Range[2000],Count[Flatten[IntegerDigits/@(#^Range[5])],0]==0&] (* Harvey P. Dale, Jun 10 2017 *)
  • PARI
    is_A253644(n,K=5)=!forstep(k=K,1,-1,vecmin(digits(n^k))||return)