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A236749
Positive integers n such that n^2 divided by the digital sum of n is a cube.
3
1, 8, 81, 512, 1000, 2592, 6400, 8000, 10125, 19683, 20736, 34300, 35937, 36125, 46656, 59319, 74088, 81000, 123823, 125000, 157464, 185193, 268912, 279936, 328509, 373248, 421875, 431244, 469567, 474552, 481474, 512000, 592704, 658503, 795906, 804357
OFFSET
1,2
EXAMPLE
2592 is in the sequence because the digital sum of 2592 is 18, and 2592^2/18 = 373248 = 72^3.
PROG
(PARI)
s=[]; for(n=1, 100000, d=sumdigits(n); if(n^2%d==0 && ispower(n^2\d, 3), s=concat(s, n))); s
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Colin Barker, Jan 30 2014
STATUS
approved