A139308 Lucky numbers that are pure (perfect) powers with exponent greater than 2.

729, 2187, 29791, 50625, 50653, 83521, 130321, 132651, 166375, 185193, 226981, 300763, 707281, 804357, 823543, 1295029, 1860867, 1874161, 2685619, 3176523, 4782969, 5545233, 5764801, 7189057, 9393931, 12977875, 13845841, 16194277

Offset

1,1

Comments

Intersection of A000959 and A076467.

Links

Kevin P. Thompson, Table of n, a(n) for n = 1..113 (terms < 10^10 with terms 1..94 from Giovanni Resta)

Example

a(1) = 729 = 3^6 and 729 is lucky, i.e., A000959(118) = 729.

Mathematica

t = 2 Range@ 10000000 - 1; f[n_] := Block[{k = t[[n]]}, t = Delete[t, Table[{k}, {k, k, Length@t, k}]]]; Do[f@n, {n, 2, 1000000}]; fQ[n_] := ! IntegerQ@ Log[2, n] && GCD @@ Last /@ FactorInteger@n > 2; Select[t, fQ] (* Robert G. Wilson v, Oct 16 2010 *)

Crossrefs

Cf. A000959, A076467, A031162.

Sequence in context: A232925 A255112 A255627 * A295024 A167728 A050220

Adjacent sequences: A139305 A139306 A139307 * A139309 A139310 A139311

Keyword

nonn

Author

Walter Kehowski, Jun 07 2008

Extensions

a(16)-a(28) from Robert G. Wilson v, Oct 16 2010

Status

approved