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A236749 Positive integers n such that n^2 divided by the digital sum of n is a cube. 3

%I

%S 1,8,81,512,1000,2592,6400,8000,10125,19683,20736,34300,35937,36125,

%T 46656,59319,74088,81000,123823,125000,157464,185193,268912,279936,

%U 328509,373248,421875,431244,469567,474552,481474,512000,592704,658503,795906,804357

%N Positive integers n such that n^2 divided by the digital sum of n is a cube.

%e 2592 is in the sequence because the digital sum of 2592 is 18, and 2592^2/18 = 373248 = 72^3.

%o (PARI)

%o s=[]; for(n=1, 100000, d=sumdigits(n); if(n^2%d==0 && ispower(n^2\d, 3), s=concat(s, n))); s

%Y Cf. A007953, A236748, A236750, A236751.

%K nonn,base

%O 1,2

%A _Colin Barker_, Jan 30 2014

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Last modified February 1 12:28 EST 2023. Contains 359993 sequences. (Running on oeis4.)