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 A110430 Arithmetic mean of all n-digit positive even numbers. 2
 5, 54, 549, 5499, 54999, 549999, 5499999, 54999999, 549999999, 5499999999, 54999999999, 549999999999, 5499999999999, 54999999999999, 549999999999999, 5499999999999999, 54999999999999999, 549999999999999999, 5499999999999999999 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS FORMULA a(n) =1/2{10^(n-1) + 10^n -2} EXAMPLE a(2) = Arithmetic mean of 10,12,14,...96,98 =(10 + 98)/2 =54. MATHEMATICA Table[FromDigits[PadRight[{5, 4}, n, 9]], {n, 20}] (* Harvey P. Dale, Apr 24 2020 *) CROSSREFS Sequence in context: A268882 A229298 A087125 * A110432 A215542 A304322 Adjacent sequences: A110427 A110428 A110429 * A110431 A110432 A110433 KEYWORD base,easy,nonn AUTHOR Amarnath Murthy, Aug 02 2005 EXTENSIONS Corrected and extended by Joshua Zucker, May 10 2006 STATUS approved

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Last modified November 26 20:01 EST 2022. Contains 358362 sequences. (Running on oeis4.)