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A066873 Number of amicable pairs where smaller term of the pair is less than 10^n. 3
0, 0, 1, 5, 13, 42, 108, 236, 586, 1427, 3340, 7642, 17519, 39374, 87102, 190775, 415523, 901312, 1947667, 4197267 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,4
LINKS
Sergei Chernykh, Amicable pairs list.
Shyam Sunder Gupta, Amicable Numbers.
J. O. M. Pedersen, Known Amicable Pairs. [Broken link; WayBackMachine archive.]
J. O. M. Pedersen, Tables of Aliquot Cycles. [Broken link; WayBackMachine archive.]
J. O. M. Pedersen, Tables of Aliquot Cycles [Cached copy, pdf file only]
EXAMPLE
There are 13 pairs with smaller term of the pair < 10^5, so a(5) = 13.
CROSSREFS
Cf. A063990, A259180 (amicable pairs).
Sequence in context: A012172 A316536 A211383 * A105262 A298234 A129789
KEYWORD
nonn,more
AUTHOR
Shyam Sunder Gupta, Jan 21 2002
EXTENSIONS
Edited by Klaus Brockhaus, May 31 2003
a(15)-a(18) (from Sergei Chernykh's site) added by Amiram Eldar, Aug 19 2017
a(19) (from Sergei Chernykh's site) added by Amiram Eldar, Apr 05 2019
a(20) (from Sergei Chernykh's site) added by Amiram Eldar, Dec 13 2020
STATUS
approved

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Last modified March 18 22:56 EDT 2024. Contains 370952 sequences. (Running on oeis4.)