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A108057
G.f. (x-1)*(x^2+1)*(x^7-x^6+x^4+x^3-2*x^2-x-1)/((x^2-x+1)*(x^6-x^3+1)*(x+1)^2).
0
1, -1, 3, -6, 7, -9, 10, -11, 13, -16, 17, -19, 22, -23, 25, -26, 27, -29, 32, -33, 35, -38, 39, -41, 42, -43, 45, -48, 49, -51, 54, -55, 57, -58, 59, -61, 64, -65, 67, -70, 71, -73, 74, -75, 77, -80, 81, -83, 86, -87, 89, -90, 91, -93, 96, -97, 99, -102, 103, -105, 106, -107, 109, -112, 113, -115, 118, -119, 121, -122
OFFSET
0,3
COMMENTS
Floretion Algebra Multiplication Program, FAMP Code: 4jbasesumseq[A*B+B*A] with A = + .25'i + .25i' + .25'ii' + .25'jj' + .25'kk' + .25'jk' + .25'kj' + .25e and B = + .5'i - .5'k - .5'jj' - .5'ji' - .5'jk' + .5e
MATHEMATICA
CoefficientList[Series[(x-1)(x^2+1)(x^7-x^6+x^4+x^3-2x^2-x-1)/((x^2-x+ 1) (x^6-x^3+1)(x+1)^2), {x, 0, 80}], x] (* or *) Join[{1}, LinearRecurrence[ {-1, 0, 0, 0, 0, 0, 0, 0, -1, -1}, {-1, 3, -6, 7, -9, 10, -11, 13, -16, 17}, 80]] (* Harvey P. Dale, Apr 17 2014 *)
CROSSREFS
Sequence in context: A267983 A344153 A334521 * A190189 A129414 A157319
KEYWORD
sign,easy
AUTHOR
Creighton Dement, Jun 02 2005
STATUS
approved