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 A199023 (6*11^n - 1) / 5. 6
 1, 13, 145, 1597, 17569, 193261, 2125873, 23384605, 257230657, 2829537229, 31124909521, 342374004733, 3766114052065, 41427254572717, 455699800299889, 5012697803298781, 55139675836286593, 606536434199152525 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Sum of n-th row of triangle of powers of 11: 1; 1 11 1; 1 11 121 11 1; 1 11 121 1331 121 11 1; ... - Philippe Deléham, Feb 23 2014 LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..900 Index entries for linear recurrences with constant coefficients, signature (12,-11). FORMULA a(n) = 11*a(n-1)+2. a(n) = 12*a(n-1)-11*a(n-2), n>1. G.f.: (1 + x)/(1 - 12*x + 11*x^2). - Vincenzo Librandi, Jan 04 2013 a(n) = Sum_{k=0..n} A112468(n,k)*12^k. - Philippe Deléham, Feb 23 2014 EXAMPLE a(0) = 1; a(1) = 1 + 11 + 1 = 13; a(2) = 1 + 11 + 121 + 11 + 1 = 145; a(3) = 1 + 11 + 121 + 1331 + 121 + 11 + 1 = 1597; etc. - Philippe Deléham, Feb 23 2014 MATHEMATICA CoefficientList[Series[(1 + x)/(1 - 12*x + 11*x^2), {x, 0, 30}], x] (* Vincenzo Librandi, Jan 04 2013 *) PROG (Magma) [(6*11^n-1)/5 : n in [0..20]] (PARI) a(n)=(6*11^n-1)/5 \\ Charles R Greathouse IV, Oct 07 2015 CROSSREFS Cf. A112468, A112739. Sequence in context: A038492 A270579 A297223 * A152585 A014881 A048442 Adjacent sequences: A199020 A199021 A199022 * A199024 A199025 A199026 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, Nov 02 2011 STATUS approved

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Last modified December 2 16:29 EST 2023. Contains 367525 sequences. (Running on oeis4.)