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A111227 Numbers n where A019294(n) > n. 4
3, 11, 29, 53, 58, 59, 67, 101, 109, 131, 149, 173, 202, 239, 461, 479, 659, 1031, 1319, 1579, 1847 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A number n is called (m,k)-perfect if sigma^m(n) = k*n. A019294(n) gives minimal values of m for n. a(n) are the values where A019294(n) > n.

Corresponding values of m and k are in A111726, A111727.

LINKS

Table of n, a(n) for n=1..21.

Graeme L. Cohen and Herman J. J. te Riele, Iterating the sum-of-divisors function Experimental Mathematics, 5 (1996), p 94.

PROG

(Haskell)

a111227 n = a111227_list !! (n-1)

a111227_list = filter (\x -> a019294 x > x) [1..]

-- Reinhard Zumkeller, Aug 02 2012

CROSSREFS

Sequence in context: A269891 A272000 A196190 * A111693 A100032 A069350

Adjacent sequences:  A111224 A111225 A111226 * A111228 A111229 A111230

KEYWORD

hard,nonn

AUTHOR

Lambert Klasen (lambert.klasen(AT)gmx.net), Oct 26 2005

STATUS

approved

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Last modified October 28 10:46 EDT 2020. Contains 338054 sequences. (Running on oeis4.)