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A323330 Larger of amicable pair m < n defined by t(n) = m and t(m) = n where t(n) = psi(n) - n and psi(n) = A001615(n) is the Dedekind psi function. 4
1550, 3100, 4790, 6200, 7750, 9580, 12400, 12922, 15500, 15290, 19160, 20330, 23950, 24800, 25844, 31000, 30580, 38320, 38750, 40660, 47900, 49600, 51688, 62000, 61160, 76640, 77500, 82150, 81320, 76450, 95800, 90454, 99200, 103376, 101650, 119750, 124000, 122320 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The terms are ordered according to the order of their lesser counterparts (A323329).

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..1000

MATHEMATICA

psi[n_] := n*Times@@(1+1/Transpose[FactorInteger[n]][[1]]); t[n_]:= psi[n] - n; s={}; Do[n=t[m]; If[n>m && t[n]==m, AppendTo[s, n]], {m, 1, 120000}]; s

CROSSREFS

Cf. A001615, A002046, A033845 (Dedekind psi perfect numbers), A323327, A323328, A323329.

Sequence in context: A336221 A020408 A259424 * A252403 A252053 A252046

Adjacent sequences:  A323327 A323328 A323329 * A323331 A323332 A323333

KEYWORD

nonn

AUTHOR

Amiram Eldar, Jan 11 2019

STATUS

approved

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Last modified December 5 20:39 EST 2021. Contains 349558 sequences. (Running on oeis4.)