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A110756
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a(n) = tau(N), where N = concatenation 1,2,3,...,n.
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5
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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; internal format)
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OFFSET
| 1,2
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FORMULA
| a(n) = A000005[A007908(n)]. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 10 2007
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EXAMPLE
| a(3) = tau(123) = 4.
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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 (mathar(AT)strw.leidenuniv.nl), Feb 10 2007
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CROSSREFS
| Cf. A110757, A110758, A110759, A110760.
Sequence in context: A198840 A021612 A201587 * A200698 A013661 A019174
Adjacent sequences: A110753 A110754 A110755 * A110757 A110758 A110759
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KEYWORD
| base,hard,nonn
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Aug 11 2005
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EXTENSIONS
| More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 10 2007
More terms from David Wasserman (dwasserm(AT)earthlink.net), Dec 22 2008
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