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A099606
Row sums of triangle A099605, in which row n equals the inverse Binomial transform of column n of the triangle A034870 of even-indexed rows of Pascal's triangle.
1
1, 4, 10, 48, 116, 560, 1352, 6528, 15760, 76096, 183712, 887040, 2141504, 10340096, 24963200, 120532992, 290992384, 1405035520, 3392055808, 16378294272, 39540700160, 190919389184, 460920178688, 2225519493120, 5372879343616
OFFSET
0,2
FORMULA
a(n) = Pell(n+1)*2^[(n+1)/2]. a(n) = 12*a(n-2) - 4*a(n-4) for n>=4. G.f.: (1+4*x-2*x^2)/(1-12*x^2+4*x^4).
EXAMPLE
Sequence begins: {1*1, 2*2, 5*2, 12*4, 29*4, 70*8, 169*8, 408*16, ...}.
PROG
(PARI) a(n)=polcoeff((1+4*x-2*x^2)/(1-12*x^2+4*x^4)+x*O(x^n), n)
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Oct 25 2004
STATUS
approved