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 A103819 Whitney transform of Jacobsthal numbers. 0
 0, 1, 3, 8, 23, 63, 172, 471, 1287, 3516, 9607, 26247, 71708, 195911, 535239, 1462300, 3995079, 10914759, 29819676, 81468871, 222577095, 608091932, 1661338055, 4538859975, 12400396060, 33878512071, 92557816263, 252872656668 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS The Whitney transform maps the sequence with g.f. g(x) to that with g.f. (1/(1-x))g(x(1+x)). LINKS Table of n, a(n) for n=0..27. Index entries for linear recurrences with constant coefficients, signature (2,2,1,-2,-2). FORMULA G.f.: x(1+x)/((1-x)(1+x+x^2)(1-2x-2x^2)); a(n)=2a(n-1)+2a(n-2)+a(n-3)-2a(n-4)-2a(n-5); a(n)=sum{k=0..n, sum{i=0..n, C(k, i-k)}*A001045(k)}. 9*a(n) = -2 +2*(A002605(n)+2*A002605(n+1))-A099837(n+3). - R. J. Mathar, Oct 23 2011 CROSSREFS Cf. A004070, A001045. Sequence in context: A146998 A261329 A248870 * A147484 A316980 A331321 Adjacent sequences: A103816 A103817 A103818 * A103820 A103821 A103822 KEYWORD easy,nonn AUTHOR Paul Barry, Feb 16 2005 STATUS approved

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Last modified September 28 17:13 EDT 2023. Contains 365736 sequences. (Running on oeis4.)