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 A046755 Numbers k such that d(k)^3 divides k. 5
 1, 625, 6561, 21952, 32768, 64000, 98304, 117649, 163840, 229376, 360448, 425984, 557056, 622592, 753664, 950272, 1015808, 1212416, 1343488, 1362944, 1409024, 1540096, 1736704, 1933312, 1998848, 2195456, 2326528, 2392064, 2588672 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Proper subset of both A033950 and A046754. If two terms in the sequence are coprime then their product is also in the sequence. LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..1000 from Donovan Johnson) EXAMPLE If k = 21952, d(k) = sigma(0,k) = 28. Its 3rd power is 21952, which divides k. a(103) = 14385152 = (2^15)*439 with 32 divisors and 14385152/(32^3) = 439; 2^15*prime is a typical form of terms in the sequence that have 32 divisors. MATHEMATICA Select[ Range[ 1, 14500000 ], IntegerQ[ #/(DivisorSigma[ 0, # ])^3 ]& ] CROSSREFS Cf. A033950, A046754, A046756. Sequence in context: A307481 A262798 A250431 * A016816 A046756 A143026 Adjacent sequences:  A046752 A046753 A046754 * A046756 A046757 A046758 KEYWORD nonn AUTHOR STATUS approved

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Last modified September 27 03:05 EDT 2021. Contains 347673 sequences. (Running on oeis4.)