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A114203
Row sums of a Pascal-Jacobsthal triangle.
4
1, 2, 4, 8, 18, 44, 110, 272, 662, 1596, 3838, 9240, 22286, 53812, 129974, 313888, 757878, 1829644, 4416910, 10662952, 25742302, 62147556, 150038438, 362226480, 874493446, 2111213372, 5096916094, 12305037368, 29706982638, 71719002644, 173145004310, 418009044032
OFFSET
0,2
COMMENTS
Binomial transform of double Jacobsthal sequence 1,1,1,1,3,3,5,5,11,11,... Row sums of A114202.
LINKS
Sergio Falcón, Binomial Transform of the Generalized k-Fibonacci Numbers, Communications in Mathematics and Applications (2019) Vol. 10, No. 3, 643-651.
FORMULA
G.f.: (1-x)^2/((1 - 2*x - x^2)*(1 - 2*x + 2*x^2)).
a(n) = 4*a(n-1) - 5*a(n-2) + 2*a(n-3) + 2*a(n-4).
a(n) = Sum_{k=0..n} Sum_{i=0..n-k} C(n-k, i)*C(k, i)*J(i).
a(n) = Sum_{k=0..n} C(n, k)*J(floor((k+2)/2)), J(n) = A001045(n).
E.g.f.: exp(x)*(cos(x) + 2*cosh(sqrt(2)*x) + sin(x) + sqrt(2)*sinh(sqrt(2)*x))/3. - Stefano Spezia, May 29 2024
MATHEMATICA
LinearRecurrence[{4, -5, 2, 2}, {1, 2, 4, 8}, 40] (* Harvey P. Dale, Jun 05 2012 *)
CROSSREFS
Sequence in context: A193617 A233139 A308246 * A339837 A100132 A176720
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Nov 16 2005
STATUS
approved