A278029 a(1) = 0; for n > 1, a(n) = k if n is a non-perfect-power, A007916(k); or 0 if n is a perfect power.

0, 1, 2, 0, 3, 4, 5, 0, 0, 6, 7, 8, 9, 10, 11, 0, 12, 13, 14, 15, 16, 17, 18, 19, 0, 20, 0, 21, 22, 23, 24, 0, 25, 26, 27, 0, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 0, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 0, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 0

Offset: 1

Author

N. J. A. Sloane, Nov 10 2016

Keywords

• nonn
• easy

Links

• Rémy Sigrist, Table of n, a(n) for n = 1..10000
• N. J. A. Sloane, Maple programs for A007916, A278028, A278029, A052409, A089723, A277564

Crossrefs

Cf. A007916, A072813, A289023.

Programs

Mathematica

FoldList[Boole[#2 != #1] #2 &, #] &@ Accumulate@ Array[Boole[And[# > 1, CoprimeQ @@ FactorInteger[#][[All, -1]]]] &, 81] (* Michael De Vlieger, Dec 18 2016 *)

Extensions

Name corrected by Peter Munn, Feb 28 2024