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A111734 Expansion of (1-x)*(2*x^2+2*x+1)/((x^2-x-1)*(x^2+x+1)). 1
-1, 1, -1, 3, -6, 10, -15, 23, -37, 61, -100, 162, -261, 421, -681, 1103, -1786, 2890, -4675, 7563, -12237, 19801, -32040, 51842, -83881, 135721, -219601, 355323, -574926, 930250, -1505175, 2435423, -3940597, 6376021, -10316620, 16692642, -27009261, 43701901, -70711161, 114413063 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

REFERENCES

C. Dement, Floretion Integer Sequences (work in progress)

LINKS

Table of n, a(n) for n=1..40.

Index entries for linear recurrences with constant coefficients, signature (-2,-1,0,1).

FORMULA

a(n) = ((-1)^n/2)*A007039(n); a(n) + a(n+1) + a(n+2) = ((-1)^n)*A000204(n)

a(n) = (-1)^n*(n*sum((binomial(n-2*m,2*m))/(n-2*m),m,0,floor((n-1)/2))). [Vladimir Kruchinin, Mar 10 2013]

MAPLE

Floretion Algebra Multiplication Program, FAMP Code: 2tesseq[(.5'j + .5'k + .5j' + .5k' + .5'ij' - .5'ik' + .5'ji' + .5'ki')*(.5'i + .5'j + .5'k + .5e)]

CROSSREFS

Cf. A000204, A007039.

Sequence in context: A063542 A262927 A122554 * A117457 A024674 A026104

Adjacent sequences:  A111731 A111732 A111733 * A111735 A111736 A111737

KEYWORD

easy,sign

AUTHOR

Creighton Dement, Nov 18 2005

STATUS

approved

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Last modified August 18 23:54 EDT 2017. Contains 290782 sequences.