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A333954 Numbers k such that A330575(k) = A330575(k+1). 0
14, 16101, 72926, 97101, 2872701, 7610324 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(7) > 6*10*8.

LINKS

Table of n, a(n) for n=1..6.

Thomas Fink, Recursively divisible numbers, arXiv:1912.07979 [math.NT], 2019.

EXAMPLE

14 is a term since A330575(14) = A330575(15) = 26.

MATHEMATICA

s[1] = 1; s[n_] := s[n] = n + DivisorSum[n, s[#] &, # < n &]; seq = {}; s1 = s[1]; Do[s2 = s[n]; If[s1 == s2, AppendTo[seq, n-1]]; s1 = s2, {n, 2, 10^5}]; seq

CROSSREFS

Cf. A330575.

Similar sequences: A002961, A064115, A064125, A293183, A306985.

Sequence in context: A048913 A246623 A208194 * A104376 A053870 A283840

Adjacent sequences: A333951 A333952 A333953 * A333955 A333956 A333957

KEYWORD

nonn,more

AUTHOR

Amiram Eldar, Apr 11 2020

STATUS

approved

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Last modified February 9 08:04 EST 2023. Contains 360153 sequences. (Running on oeis4.)