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A054002 Number of divisors of n such that n and n-1 have the same sum of divisors. 2
4, 6, 4, 8, 16, 8, 8, 12, 12, 8, 4, 10, 8, 4, 8, 12, 8, 16, 16, 16, 16, 8, 16, 12, 16, 16, 8, 8, 4, 16, 8, 24, 16, 4, 16, 8, 4, 32, 8, 16, 16, 16, 8, 8, 8, 8, 16, 32, 8, 8, 16, 16, 16, 12, 16, 16, 12, 8, 48, 32, 8, 24, 24, 16, 16, 16, 8, 16, 24, 64, 8, 16, 16, 16, 16, 64, 24, 32, 60 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..79.

FORMULA

a(n) = tau(A002961(n) + 1)

CROSSREFS

Cf. A000005, A000203, A002961, A053249, A054003.

Sequence in context: A055166 A202243 A130762 * A010300 A113209 A088739

Adjacent sequences:  A053999 A054000 A054001 * A054003 A054004 A054005

KEYWORD

nonn

AUTHOR

Asher Auel (asher.auel(AT)reed.edu) Jan 12, 2000

EXTENSIONS

More terms from Naohiro Nomoto, Jun 23 2001

STATUS

approved

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Last modified February 16 02:32 EST 2019. Contains 320140 sequences. (Running on oeis4.)