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A104021
Numbers that can be represented as k^2*j with 0 < j <= k and gcd(k, j) = 1.
5
4, 9, 16, 18, 25, 36, 48, 49, 50, 64, 75, 81, 98, 100, 121, 144, 147, 162, 169, 180, 192, 196, 225, 242, 245, 256, 289, 294, 300, 320, 324, 338, 361, 363, 400, 405, 441, 448, 450, 484, 507, 529, 567, 576, 578, 588, 605, 625, 648, 676, 700, 720, 722, 726, 729
OFFSET
1,1
COMMENTS
Essentially the same as A102646. - Georg Fischer, Oct 07 2018
MATHEMATICA
Take[ Union[ Flatten[ Table[ If[ GCD[k, j] == 1, k^2*j, {}], {k, 27}, {j, k - 1}]]], 55]
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved