A364948 Perfect powers that are equal to the sum of the first k perfect powers > 1 for some k.

4, 121, 2548735225

Offset

1,1

Links

Table of n, a(n) for n=1..3.

Example

121 is a term because 121 = 11^2 = 4 + 8 + 9 + 16 + 25 + 27 + 32 = 2^2 + 2^3 + 3^2 + 2^4 + 5^2 + 3^3 + 2^5.

Mathematica

Select[Accumulate[Select[Range[3723875], GCD @@ FactorInteger[#][[All, 2]] > 1 &]], GCD @@ FactorInteger[#][[All, 2]] > 1 &]

Crossrefs

Cf. A001597, A013918, A013921, A013932.

Sequence in context: A144508 A169972 A360664 * A080179 A268050 A268006

Adjacent sequences: A364945 A364946 A364947 * A364949 A364950 A364951

Keyword

nonn,bref,hard,more

Author

Ilya Gutkovskiy, Aug 14 2023

Status

approved