A082950 Power base and exponent of n-th prime power exchanged.

0, 1, 1, 4, 1, 1, 9, 8, 1, 1, 16, 1, 1, 1, 32, 27, 1, 1, 25, 1, 1, 1, 1, 128, 1, 1, 1, 36, 1, 1, 1, 1, 64, 1, 1, 1, 1, 1, 1, 1, 1, 2048, 243, 1, 49, 1, 1, 1, 1, 1, 1, 1, 1, 8192, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 125, 1, 64, 1, 1, 1, 1, 1, 1, 1, 131072, 1, 1, 1, 1, 1, 1, 1, 2187, 1, 1, 1, 1

Offset

1,4

Links

Table of n, a(n) for n=1..91.

Formula

a(n) = A025474(n)^A025473(n) while A025473(n)^A025474(n) = A000961(n).

a(n) = 1 iff A000961(n) is prime.

Mathematica

s[n_] := Module[{f = FactorInteger[n]}, If[Length[f] == 1, f[[1, 2]]^f[[1, 1]], Nothing]]; s[1] = 0; Array[s, 250] (* Amiram Eldar, May 16 2025 *)

Crossrefs

Cf. A000961, A025473, A025474.

Sequence in context: A141905 A110511 A114188 * A060102 A308359 A199065

Adjacent sequences: A082947 A082948 A082949 * A082951 A082952 A082953

Keyword

nonn

Author

Reinhard Zumkeller, May 26 2003

Extensions

a(71) and following corrected by Georg Fischer, Dec 09 2022

Status

approved