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A131041
a(n) = 2*a(n-1) - a(n-2) - a(n-4).
3
1, 1, 1, -1, -4, -8, -13, -17, -17, -9, 12, 50, 105, 169, 221, 223, 120, -152, -645, -1361, -2197, -2881, -2920, -1598, 1921, 8321, 17641, 28559, 37556, 38232, 21267, -24257, -107337, -228649, -371228, -489550, -500535, -282871, 306021
OFFSET
0,5
COMMENTS
Generating floretion is .5i' + .5j' + .5k' + .5e + 'ii' (for A131039 it is 'i + .5i' + .5j' + .5k' + .5e and for A131040 it is 1.5i' + .5j' + .5k' + .5e)
FORMULA
G.f. (1-x-2*x^3)/(1-2*x+x^2+x^4)
MAPLE
Floretion Algebra Multiplication Program, FAMP Code: 2tesseq[.5i' + .5j' + .5k' + .5e + 'ii']
MATHEMATICA
LinearRecurrence[{2, -1, 0, -1}, {1, 1, 1, -1}, 40] (* Harvey P. Dale, Oct 14 2012 *)
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Creighton Dement, Jun 11 2007
STATUS
approved