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A110756 a(n) = tau(N), where N = concatenation 1,2,3,...,n. 5
1, 6, 4, 4, 8, 28, 4, 24, 12, 8, 64, 32, 8, 8, 8, 12, 24, 48, 64, 192, 256, 64, 16, 48, 24, 160, 96, 64, 16, 128, 8, 48, 64, 4, 192, 120, 16, 16, 64, 384, 32, 128, 16, 48, 768, 128, 32, 192, 64, 768, 8, 32, 64, 1792, 32, 24 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..56.

FORMULA

a(n) = A000005[A007908(n)]. - R. J. Mathar, Feb 10 2007

EXAMPLE

a(3) = tau(123) = 4.

MAPLE

A055642 := proc(n) 1+floor(log10(n)) ; end; A000005 := proc(n) numtheory[tau](n) ; end ; A007908 := proc(n) local a ; a := 1 ; for i from 2 to n do a := a*10^A055642(i)+i ; end; RETURN(a) ; end; A110756 := proc(n) A000005(A007908(n)) ; end; for n from 1 to 50 do printf("%d %d ", n, A110756(n)) ; od ; # R. J. Mathar, Feb 10 2007

CROSSREFS

Cf. A110757, A110758, A110759, A110760.

Sequence in context: A211268 A021612 A201587 * A200698 A013661 A209273

Adjacent sequences:  A110753 A110754 A110755 * A110757 A110758 A110759

KEYWORD

base,hard,nonn

AUTHOR

Amarnath Murthy, Aug 11 2005

EXTENSIONS

More terms from R. J. Mathar, Feb 10 2007

More terms from David Wasserman, Dec 22 2008

STATUS

approved

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Last modified October 20 19:34 EDT 2018. Contains 316401 sequences. (Running on oeis4.)