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A162284 Odd numbers n such that b(n) >= n and b(b(n)) >= n, where b(n) = A161942(n) = oddpart(sigma(n)). 1
1, 81, 18966025, 135187129, 164275489, 350561925, 445421025, 598047025, 649587169, 748733769, 850830561, 960362325, 1055925025, 1341097641, 1406175001, 1476326929, 1520766009, 1536248025, 1591004025, 1735566525 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Applying b a third time produces a smaller value for every number in this sequence up to 10^10, except 1.

LINKS

Robert Gerbicz, Table of n,a(n) up to 10^10; n=1..43

CROSSREFS

Cf. A161942.

Sequence in context: A033435 A013851 A092258 * A116268 A128838 A051001

Adjacent sequences:  A162281 A162282 A162283 * A162285 A162286 A162287

KEYWORD

nonn

AUTHOR

Franklin T. Adams-Watters (FrankTAW(AT)Netscape.net), Jun 29 2009

EXTENSIONS

Values for n > 3 from Robert Gerbicz (robert.gerbicz(AT)gmail.com)

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Last modified February 14 18:47 EST 2012. Contains 205663 sequences.