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.

Showing 1-2 of 2 results.

A385516 Perfect powers whose digits are in strictly decreasing order.

Original entry on oeis.org

1, 4, 8, 9, 32, 64, 81, 841, 961
Offset: 1

Views

Author

Stefano Spezia, Jul 01 2025

Keywords

Crossrefs

Cf. A001597, A009995, A355060, A355062, A355063, A385517.

Programs

  • Mathematica
    perfectPowerQ[n_] := n==1 || GCD @@ FactorInteger[n][[All, 2]] > 1; (* A001597 *) Select[Range[1000], perfectPowerQ[#] && Max[Differences[IntegerDigits[#]]]<0 &]

A385517 Perfect powers whose digits are in nonincreasing order.

Original entry on oeis.org

1, 4, 8, 9, 32, 64, 81, 100, 400, 441, 841, 900, 961, 1000, 6400, 7744, 7776, 8000, 8100, 10000, 40000, 44100, 64000, 84100, 90000, 96100, 100000, 640000, 774400, 810000, 1000000, 3200000, 4000000, 4410000, 8000000, 8410000, 8874441, 9000000, 9610000, 9853321, 10000000
Offset: 1

Views

Author

Stefano Spezia, Jul 01 2025

Keywords

Crossrefs

Cf. A001597, A009995, A355060, A355062, A355063, A385516.

Programs

  • Mathematica
    perfectPowerQ[n_] :=n==1 || GCD @@ FactorInteger[n][[All, 2]] > 1; (* A001597 *) Select[Range[10^6], perfectPowerQ[#] && Max[Differences[IntegerDigits[#]]]<1 &]
Showing 1-2 of 2 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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