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A181596 Abundance of A181595(n). 7
4, 3, 2, 12, 10, 8, 4, 2, 7, 56, 78, 8, 2, 2, 32, 16, 4, 2, 532, 152, 136, 8, 68, 31, 992, 128, 8, 64, 32, 16, 4, 8, 128, 32, 8, 2, 43648, 2528, 32, 4, 2, 32, 2272, 32, 32, 127, 16256, 32, 32, 4, 536, 8, 32, 8, 52, 16, 32, 41044, 64, 512, 128, 64, 16, 4, 2, 8 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) is a proper divisor of A181595(n).

LINKS

Michel Marcus, Table of n, a(n) for n = 1..200

Paul Pollack and Vladimir Shevelev, On perfect and near-perfect numbers, J. Number Theory 132 (2012), pp. 3037-3046. arXiv:1011.6160

FORMULA

a(n) = A033880(A181595(n)).

EXAMPLE

Since A181595(1)=12, a(1)=sigma(12)-2*12=28-24=4.

CROSSREFS

Cf. A181595, A000396, A005101, A153501, A005820.

Sequence in context: A065367 A033882 A062111 * A182142 A033881 A099406

Adjacent sequences:  A181593 A181594 A181595 * A181597 A181598 A181599

KEYWORD

nonn

AUTHOR

Vladimir Shevelev, Nov 01 2010

EXTENSIONS

I corrected a(10) and a(11) Vladimir Shevelev, Nov 03 2010

Entries checked, definition shortened - R. J. Mathar, Nov 17 2010

More terms from Michel Marcus, Feb 06 2016

STATUS

approved

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Last modified March 30 04:57 EDT 2017. Contains 284297 sequences.