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A133603
The matrix-vector product A133566 * A000108.
2
1, 1, 3, 5, 19, 42, 174, 429, 1859, 4862, 21658, 58786, 266798, 742900, 3417340, 9694845, 45052515, 129644790, 607283490, 1767263190, 8331383610, 24466267020, 115948830660, 343059613650, 1632963760974, 4861946401452
OFFSET
0,3
COMMENTS
A133602 is a companion sequence.
FORMULA
A133566 * A000108 where A133566 = an infinite lower triangular matrix and A000108 = the Catalan sequence. For odd n, a(n) = C(n). For even n, a(n) = C(n) + C(n-1) = A005807(n-1).
Conjecture: n*(n-2)*(3*n-1)*(n+1)*a(n) -8*n*(2*n-3)*a(n-1) -4*(n-1)*(3*n+2)*(
2*n-3)*(2*n-5)*a(n-2)=0. - R. J. Mathar, Jun 20 2015
EXAMPLE
a(5) = C(5) = 42.
a(6) = 174 = C(6) + C(5) = 132 + 42.
MAPLE
A133603 := proc(n)
add(A133566(n+1, k+1)*A000108(k), k=0..n) ;
end proc: # R. J. Mathar, Jun 20 2015
CROSSREFS
Cf. A133566, A000108, A133602, A024492 (bisection).
Sequence in context: A242818 A218373 A034511 * A201867 A148534 A148535
KEYWORD
nonn,easy
AUTHOR
Gary W. Adamson, Sep 18 2007
STATUS
approved