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 A293188 Unitary pseudoperfect numbers: numbers n that equal to the sum of a subset of their aliquot unitary divisors. 10
 6, 30, 42, 60, 66, 78, 90, 102, 114, 138, 150, 174, 186, 210, 222, 246, 258, 282, 294, 318, 330, 354, 366, 390, 402, 420, 426, 438, 462, 474, 498, 510, 534, 546, 570, 582, 606, 618, 630, 642, 654, 660, 678, 690, 714, 726, 750, 762, 770, 780, 786, 798, 822 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Supersequence of A002827. The nonsquarefree terms are 60, 90, 150, 294, 420, 630, 660, 726, 750, 780, 840, ... LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 EXAMPLE 150 is in the sequence since its unitary aliquot divisors are 1, 2, 3, 6, 25, 50, 75 and 150 = 25 + 50 + 75. MATHEMATICA udiv[n_]:=Block[{d=Divisors[n]}, Select[d, GCD[#, n/#]==1&]]; a={}; n=0; While[Length[a]<100, n++; d=Most[udiv[n]]; c = SeriesCoefficient[ Series[ Product[1+x^d[[i]], {i, Length[d]} ], {x, 0, n}], n]; If[c>0, AppendTo[a, n]]]; a (* after T. D. Noe at A005835 *) CROSSREFS Cf. A002827, A005835, A034683, A064114. Sequence in context: A101937 A101939 A290466 * A080289 A175907 A114649 Adjacent sequences:  A293185 A293186 A293187 * A293189 A293190 A293191 KEYWORD nonn AUTHOR Amiram Eldar, Oct 01 2017 STATUS approved

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Last modified September 22 09:03 EDT 2020. Contains 337289 sequences. (Running on oeis4.)