A340049 - OEIS

%I #6 Feb 01 2021 12:36:29

%S 2,9,28,43,65,80,126,141,206,217,232,297,344,359,424,513,528,593,599,

%T 730,745,768,810,985,1001,1016,1081,1256,1332,1347,1354,1412,1587,

%U 1625,1729,1744,1809,1956,1984,2198,2213,2278,2353,2453,2627,2745,2760,2822,2825,3000

%N Numbers that are the sum of a fourth power s and a cube t such that 0 < s <= t.

%e 28 is in the sequence since 1^4 + 3^3 = 1 + 27 = 28, where 0 < 1 <= 27.

%t Table[If[Sum[(Floor[i^(1/4)] - Floor[(i - 1)^(1/4)]) (Floor[(n - i)^(1/3)] - Floor[(n - i - 1)^(1/3)]), {i, Floor[n/2]}] > 0, n, {}], {n, 1000}] // Flatten

%Y Cf. A010057.

%K nonn

%O 1,1

%A _Wesley Ivan Hurt_, Dec 26 2020