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A109785
Expansion of (1+x+x^2+x^7+x^8-2*x^10-x^12) / ((x+1)*(x^2+1)*(x^2+x+1)*(x^2-x+1)*(x^4-x^2+1)*(x-1)^2).
1
1, 2, 3, 3, 3, 3, 3, 4, 5, 5, 3, 3, 3, 4, 5, 5, 5, 5, 5, 6, 7, 7, 5, 5, 5, 6, 7, 7, 7, 7, 7, 8, 9, 9, 7, 7, 7, 8, 9, 9, 9, 9, 9, 10, 11, 11, 9, 9, 9, 10, 11, 11, 11, 11, 11, 12, 13, 13, 11, 11, 11, 12, 13, 13, 13, 13, 13, 14, 15, 15, 13, 13, 13, 14, 15, 15, 15, 15, 15, 16, 17, 17, 15, 15, 15
OFFSET
0,2
COMMENTS
Floretion Algebra Multiplication Program, FAMP Code: 1jbasesumseq[(- .5'j + .5'k - .5j' + .5k' - 'ii' - .5'ij' - .5'ik' - .5'ji' - .5'ki')*(- .5'i + .5'j - .5i' + .5j' - 'kk' - .5'ik' - .5'jk' - .5'ki' - .5'kj')], sumtype: (default, ver. f, ves)
LINKS
FORMULA
a(n) = a(n-1) + a(n-12) - a(n-13) for n>12. - Colin Barker, May 15 2019
MATHEMATICA
CoefficientList[Series[(1+x+x^2+x^7+x^8-2x^10-x^12)/((x+1)(x^2+1) (x^2+x+1) (x^2-x+1)(x^4-x^2+1)(x-1)^2), {x, 0, 90}], x] (* Harvey P. Dale, Oct 21 2011 *)
PROG
(PARI) Vec((1 + x + x^2 + x^7 + x^8 - 2*x^10 - x^12) / ((1 - x)^2*(1 + x)*(1 - x + x^2)*(1 + x^2)*(1 + x + x^2)*(1 - x^2 + x^4)) + O(x^100)) \\ Colin Barker, May 15 2019
CROSSREFS
Sequence in context: A068953 A362960 A189635 * A058224 A131808 A196183
KEYWORD
nonn,easy
AUTHOR
Creighton Dement, Aug 14 2005
STATUS
approved