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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 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: A021612 A329281 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 April 5 16:04 EDT 2020. Contains 333245 sequences. (Running on oeis4.)