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A109765
Expansion of x/((4*x-1)*(2*x-1)*(x+1)).
2
0, 1, 5, 23, 97, 399, 1617, 6511, 26129, 104687, 419089, 1677039, 6709521, 26840815, 107368721, 429485807, 1717965073, 6871903983, 27487703313, 109950988015, 439804301585, 1759217905391, 7036873019665, 28147494874863
OFFSET
0,3
COMMENTS
In reference to the program code given, 1baseksumseq[C*D] = A001045 (Jacobsthal sequence, disregard signs).
Floretion Algebra Multiplication Program, FAMP Code: 1basejsumseq[C*D] with C = - 'j + 'k - j' + k' - 'ii' - 'ij' - 'ik' - 'ji' - 'ki' and D = + .5'i + .5'k - .5j' - .5k' + .5'ii' + .5'jj' + .5'jk' + .5'ki'; sumtype: sum[Y[15]] = sum[Y[ * ]], disregard signs
FORMULA
a(n) = 5*a(n-1) - 2*a(n-2) - 8*a(n-3), n >= 3.
a(n) = (1/15)*(6*4^n-5*2^n-(-1)^n).
a(n+1) + a(n) = A006516(n+1).
a(n+2) - a(n) = A010036(n+1).
MATHEMATICA
CoefficientList[Series[x/((4x-1)(2x-1)(x+1)), {x, 0, 30}], x] (* or *)
LinearRecurrence[{5, -2, -8}, {0, 1, 5}, 30] (* Harvey P. Dale, Jan 02 2013 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Creighton Dement, Aug 13 2005
STATUS
approved