A202271 Right-truncatable perfect powers: every prefix is perfect power.

1, 4, 8, 9, 16, 49, 81, 169

Offset

1,2

Comments

Also right-truncatable powerful numbers: every prefix is powerful number. This sequence is finite with 8 terms.

Links

Table of n, a(n) for n=1..8.

Mathematica

perfectPowerQ[n_] := n == 1 || GCD @@ FactorInteger[n][[All, 2]] > 1; (* A001597 *)
Select[Range[1000], Sum[Boole[perfectPowerQ[Floor[#/10^i]]], {i, 0, IntegerLength[#]-1}] == IntegerLength[#] &] (* Stefano Spezia, Jun 27 2025 *)

Crossrefs

Cf. A001597 (perfect powers), A001694 (powerful numbers), A385401.

Sequence in context: A227243 A272575 A020145 * A334858 A162898 A385351

Adjacent sequences: A202268 A202269 A202270 * A202272 A202273 A202274

Keyword

nonn,base,fini,full

Author

Jaroslav Krizek, Jan 06 2012

Status

approved