A068783 Lesser of two consecutive numbers each divisible by a fifth power.

1215, 6560, 8991, 9375, 14336, 16767, 22112, 24543, 29888, 32319, 37664, 40095, 45440, 47871, 53216, 55647, 60992, 63423, 68768, 71199, 76544, 78975, 84320, 86751, 90624, 92096, 94527, 99872, 102303, 107648, 109375, 110079, 115424

Offset: 1

Author

Robert G. Wilson v, Mar 04 2002

Keywords

• nonn

Comments

The asymptotic density of this sequence is 1 - 2/zeta(5) + Product_{p prime} (1 - 2/p^5) = 0.000284512101137896862... - Amiram Eldar, Feb 16 2021

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..1000 from Harvey P. Dale)

Crossrefs

Cf. A068780, A068781, A068140, A068782, A068784, A068785.

Programs

Mathematica

Select[ Range[2, 250000], Max[ Transpose[ FactorInteger[ # ]] [[2]]] > 4 && Max[ Transpose[ FactorInteger[ # + 1]] [[2]]] > 4 &]
SequencePosition[Table[If[Max[FactorInteger[n][[All,2]]]>4,1,0],{n,120000}],{1,1}][[All,1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Dec 25 2018 *)