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 A067090 Floor(X/Y) where X = concatenation of (2n), (2n-1), ... down to n+1 and Y = concatenation of 1,2,3,... up to n. 9
 2, 3, 5, 7, 8, 981, 114462, 13082645, 1471900839, 1635537203, 1799173568, 1962809933, 2126446298, 2290082663, 2453719028, 2617355393, 2780991758, 2944628123, 3108264488, 3271900853, 3435537218, 3599173583, 3762809948 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..23. EXAMPLE a(4) = floor(8765/1234) = 7. a(6) = floor(121110987/123456) = floor(981.00527313374805598755832037325) = 981. MATHEMATICA f[n_] := (k = 1; x = y = "0"; While[k < n + 1, x = StringJoin[x, ToString[2n - k + 1]]; y = StringJoin[y, ToString[2k - 1]]; k++ ]; Return[ Floor[ ToExpression[x] / ToExpression[y]]] ); Table[ f[n], {n, 1, 25} ] Table[Floor[FromDigits[Flatten[IntegerDigits/@(Range[2n, n+1, -1])]]/FromDigits[Flatten[IntegerDigits/@(Range[n])]]], {n, 25}] (* Harvey P. Dale, Jul 24 2011 *) CROSSREFS Cf. A067088, A067089. Sequence in context: A105404 A238378 A075012 * A284173 A276227 A355269 Adjacent sequences: A067087 A067088 A067089 * A067091 A067092 A067093 KEYWORD easy,base,nonn AUTHOR Amarnath Murthy, Jan 07 2002 EXTENSIONS More terms from Robert G. Wilson v, Jan 09 2002 Edited by N. J. A. Sloane at the suggestion of Andrew S. Plewe, May 14 2007 Offset corrected by Sean A. Irvine, Dec 02 2023 STATUS approved

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Last modified July 25 00:10 EDT 2024. Contains 374585 sequences. (Running on oeis4.)