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 A171068 G.f. -x*(x-1)*(1+x)/(1-x-11*x^2-x^3+x^4). 1
 0, 1, 1, 11, 23, 144, 407, 2003, 6601, 28897, 103104, 425569, 1582009, 6337475, 24062039, 94930704, 364368599, 1426330907, 5505254161, 21464332033, 83084090112, 323270665729, 1253154734833, 4870751815931, 18895640474711 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS The member k=11 of a family of sequences starting 0,1,1,k with recurrence a(n) = a(n-1)+k*a(n-2)+a(n-3)-a(n-4). LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..1000 Hugh Williams, R. K. Guy, Some fourth-order linear divisibility sequences, Intl. J. Number Theory vol. 7 (5) (2011) 1255-1277 Index entries for linear recurrences with constant coefficients, signature (1,11,1,-1). FORMULA a(n)= +a(n-1) +11*a(n-2) +a(n-3) -a(n-4). MATHEMATICA CoefficientList[Series[-x*(x - 1)*(1 + x)/(1 - x - 11*x^2 - x^3 + x^4), {x, 0, 40}], x] (* Vincenzo Librandi, Dec 19 2012 *) PROG (MAGMA) I:=[0, 1, 1, 11]; [n le 4 select I[n] else Self(n-1) + 11*Self(n-2) + Self(n-3) - Self(n-4): n in [1..30]]; // Vincenzo Librandi, Dec 19 2012 CROSSREFS Cf. A116201 (k=1), A105309 (k=2), A152090 (k=3), A007598 (k=4), A005178 (k=5), A003757 (k=6). Sequence in context: A014874 A027899 A106388 * A091465 A261352 A018979 Adjacent sequences:  A171065 A171066 A171067 * A171069 A171070 A171071 KEYWORD nonn,easy AUTHOR R. J. Mathar, at the request of R. K. Guy, Sep 03 2010 STATUS approved

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Last modified April 23 22:41 EDT 2019. Contains 322389 sequences. (Running on oeis4.)