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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Essentially the same as A102646. - Georg Fischer, Oct 07 2018

LINKS

Table of n, a(n) for n=1..55.

MATHEMATICA

Take[ Union[ Flatten[ Table[ If[ GCD[k, j] == 1, k^2*j, {}], {k, 27}, {j, k - 1}]]], 55]

CROSSREFS

Cf. A102448, A104020, A104023, A104026.

Sequence in context: A066694 A235993 A102646 * A073804 A219364 A195212

Adjacent sequences:  A104018 A104019 A104020 * A104022 A104023 A104024

KEYWORD

nonn

AUTHOR

Leroy Quet and Robert G. Wilson v, Feb 24 2005

STATUS

approved

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Last modified September 17 16:50 EDT 2021. Contains 347487 sequences. (Running on oeis4.)