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A036432
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Sets a record for the number of positive integers which, when added to the number of their divisors, gives n.
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1
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1, 2, 7, 38, 122, 2766, 64686, 1972296, 5387768, 56208248, 753815160, 130065181784
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,2
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COMMENTS
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Invented by the HR concept formation program.
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LINKS
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Table of n, a(n) for n=0..11.
S. Colton, Refactorable Numbers - A Machine Invention, J. Integer Sequences, Vol. 2, 1999, #2.
S. Colton, HR - Automatic Theory Formation in Pure Mathematics
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FORMULA
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Sets record for |{b in N : b + tau(b) = n}|
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EXAMPLE
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2=1+tau(1) [ first with 1 ] 7=4+tau(4) and 5+tau(5) [ first with 2 ] 38=30+tau(30) and 32+tau(32) and 34+tau(34) [ first with 3 ]
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CROSSREFS
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Cf. A036431.
Sequence in context: A182331 A173762 A180269 * A094431 A209006 A168492
Adjacent sequences: A036429 A036430 A036431 * A036433 A036434 A036435
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KEYWORD
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hard,nonn,nice,more
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AUTHOR
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Simon Colton (simonco(AT)cs.york.ac.uk)
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EXTENSIONS
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More terms from Julian Richardson (julianr(AT)dai.ed.ac.uk), who has searched up to 100000000.
a(10)-a(11) from Donovan Johnson, Feb 19 2009
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STATUS
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approved
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