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A110758 a(n) is the number of divisors of N, where N = concatenation n times n. 4
1, 4, 6, 12, 8, 96, 8, 64, 20, 256, 96, 2304, 64, 512, 12288, 5120, 64, 5120, 8, 6144, 24576, 3072, 64, 24576, 1536, 1024, 7168, 12288, 256, 3145728, 32, 98304, 36864, 2048, 8192, 491520, 128, 128, 49152, 131072, 128, 6291456, 256, 73728, 5242880 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..45.

FORMULA

a(n) = A000005(A000461(n)). - Michel Marcus, Nov 18 2018

EXAMPLE

a(3) = tau(333) = 6.

MATHEMATICA

f[n_] := Sum[n*10^(i * Length[IntegerDigits[n]]), {i, 0, n - 1}]; Do[Print[DivisorSigma[0, f[n]]], {n, 100}] (* Ryan Propper, Jul 21 2006 *)

CROSSREFS

Cf. A000005, A000461.

Cf. A110756, A110757, A110759, A110760.

Sequence in context: A270835 A272063 A152678 * A189765 A074162 A038040

Adjacent sequences:  A110755 A110756 A110757 * A110759 A110760 A110761

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Aug 11 2005

EXTENSIONS

Corrected and extended by Ryan Propper, Jul 21 2006

STATUS

approved

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Last modified September 27 11:29 EDT 2021. Contains 347689 sequences. (Running on oeis4.)