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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, 64, 16, 16, 128, 8, 192, 24, 768, 64 (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. A000005, A007908, A110757, A110758, A110759, A110760. Sequence in context: A021612 A329281 A201587 * A200698 A013661 A209273 Adjacent sequences:  A110753 A110754 A110755 * A110757 A110758 A110759 KEYWORD nonn,base AUTHOR Amarnath Murthy, Aug 11 2005 EXTENSIONS More terms from R. J. Mathar, Feb 10 2007 More terms from David Wasserman, Dec 22 2008 a(57)-a(65) from Jinyuan Wang, May 23 2020 STATUS approved

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Last modified September 23 20:42 EDT 2021. Contains 347617 sequences. (Running on oeis4.)