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A066363 The floor[n^(3/4)]-perfect numbers, where f-perfect numbers for an arithmetical function f is defined in A066218. 1

%I #12 Sep 26 2019 09:05:51

%S 2,4,8,10,16,98,236,244,268,284,292,316,332,638,2198,2282,2338,2422,

%T 2674,4653,12274,30753,65018,225267,231478,289605,376995,422684,

%U 449756,453092,515175,521925,522825,524325,527025,527925,528225,534075,538275,539025,540975

%N The floor[n^(3/4)]-perfect numbers, where f-perfect numbers for an arithmetical function f is defined in A066218.

%H Amiram Eldar, <a href="/A066363/b066363.txt">Table of n, a(n) for n = 1..268</a>

%H J. Pe, <a href="http://jlpe.tripod.com/gpn/fperfect.htm">On a Generalization of Perfect Numbers</a>, J. Rec. Math., 31(3) (2002-2003), 168-172.

%t f[x_] := Floor[ x^(3/4)]; Select[ Range[ 2, 10^4], 2 * f[ # ] == Apply[ Plus, Map[ f, Divisors[ # ] ] ] & ]

%Y Cf. A066218.

%K nonn

%O 1,1

%A _Joseph L. Pe_, Dec 20 2001

%E a(21)-a(41) from _Amiram Eldar_, Sep 26 2019

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Last modified April 25 05:49 EDT 2024. Contains 371964 sequences. (Running on oeis4.)