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 A257289 a(n) = 8*9^n - 7*8^n. 5
 1, 16, 200, 2248, 23816, 243016, 2416520, 23583688, 226933256, 2159839816, 20378082440, 190918934728, 1778399954696, 16486635929416, 152228014061960, 1400838452135368, 12853836673840136, 117654854901535816, 1074656292809619080, 9798007424852945608 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS First differences of 9^n - 8^n = A016185. Number of numbers with n digits having the largest digit equal to 8. Note that this is independent of the base b > 8. Equivalently, number of n-letter words over a 9-letter alphabet, which must not start with the last letter of the alphabet, and in which the first letter of the alphabet must appear. LINKS Index entries for linear recurrences with constant coefficients, signature (17,-72). FORMULA G.f.: (1-x)/((1-8*x)*(1-9*x)). - Vincenzo Librandi, May 04 2015 MATHEMATICA Table[8 9^n - 7 8^n, {n, 0, 20}] (* Vincenzo Librandi, May 04 2015 *) LinearRecurrence[{17, -72}, {1, 16}, 30] (* Harvey P. Dale, May 26 2019 *) PROG (PARI) a(n)=8*9^n-7*8^n (MAGMA) [8*9^n-7*8^n: n in [0..20]]; // Vincenzo Librandi, May 04 2015 (Sage) [8*9^n-7*8^n for n in (0..20)] # Bruno Berselli, May 04 2015 CROSSREFS Cf. A016185. See also A000225, A027649, A255463, A257285 - A257288 and A088924. Sequence in context: A081679 A154249 A226869 * A125451 A154348 A129333 Adjacent sequences:  A257286 A257287 A257288 * A257290 A257291 A257292 KEYWORD nonn,easy AUTHOR M. F. Hasler, May 03 2015 STATUS approved

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Last modified June 25 17:47 EDT 2019. Contains 324353 sequences. (Running on oeis4.)