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A113837 A number k is included if d(sigma(k)) > sigma(d(k)), where d(k) is number of positive divisors of k and sigma(k) is sum of positive divisors of k. 0
5, 7, 11, 13, 14, 15, 17, 19, 22, 23, 26, 27, 29, 31, 33, 34, 35, 37, 38, 39, 41, 43, 46, 47, 51, 53, 54, 55, 56, 57, 58, 59, 61, 62, 65, 67, 69, 71, 73, 74, 77, 78, 79, 82, 83, 85, 86, 87, 88, 89, 91, 92, 93, 94, 95, 97, 101, 102, 103, 104, 106, 107, 109, 110, 111, 113, 114 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..67.

EXAMPLE

d(sigma(14)) = d(24) = 8, and sigma(d(14)) = sigma(4) = 7. Since 8 > 7, 14 is in the sequence.

MAPLE

with(numtheory): a:=proc(n) if tau(sigma(n))>sigma(tau(n)) then n else fi end: seq(a(n), n=1..122); # Emeric Deutsch, Feb 06 2006

CROSSREFS

Cf. A062068, A062069.

Sequence in context: A082684 A096379 A098761 * A255363 A245757 A240912

Adjacent sequences:  A113834 A113835 A113836 * A113838 A113839 A113840

KEYWORD

nonn

AUTHOR

Leroy Quet, Jan 23 2006

EXTENSIONS

More terms from Emeric Deutsch, Feb 06 2006

STATUS

approved

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Last modified October 18 04:46 EDT 2019. Contains 328145 sequences. (Running on oeis4.)