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 A170739 G.f.: (1+x)/(1-19*x). 50
 1, 20, 380, 7220, 137180, 2606420, 49521980, 940917620, 17877434780, 339671260820, 6453753955580, 122621325156020, 2329805177964380, 44266298381323220, 841059669245141180, 15980133715657682420, 303622540597495965980, 5768828271352423353620, 109607737155696043718780 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..200 Index entries for linear recurrences with constant coefficients, signature (19). FORMULA a(n)= Sum_{k, 0<=k<=n} A097805(n,k)*(-1)^(n-k)*20^k. - Philippe Deléham, Dec 04 2009 a(0) = 1; for n>0, a(n) = 20*19^(n-1). - Vincenzo Librandi, Dec 05 2009 a(0) = 1, a(1) = 20; for n>1, a(n) = 19*a(n-1). - Vincenzo Librandi, Dec 05 2012 MATHEMATICA Join[{1}, 20*19^Range[0, 25]] (* Vladimir Joseph Stephan Orlovsky, Jul 13 2011 *) CoefficientList[Series[(1+x)/(1-19x), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 05.2012 *) PROG (MAGMA) [1] cat [20*19^(n-1): n in [1..20]]; // Vincenzo Librandi, Dec 05 2012 (PARI) a(n)=20*19^n\19 \\ Charles R Greathouse IV, Jul 01 2013 CROSSREFS Sequence in context: A170605 A170653 A170701 * A218722 A158534 A171325 Adjacent sequences:  A170736 A170737 A170738 * A170740 A170741 A170742 KEYWORD nonn,easy AUTHOR N. J. A. Sloane, Dec 04 2009 STATUS approved

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Last modified September 21 17:46 EDT 2019. Contains 327273 sequences. (Running on oeis4.)