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A177825 Expansion of 1/((1 + x^3 - x^4)*(1 - x)). 1
1, 1, 1, 0, 1, 1, 2, 0, 1, 0, 3, 0, 2, -2, 4, -1, 5, -5, 6, -5, 11, -10, 12, -15, 22, -21, 28, -36, 44, -48, 65, -79, 93, -112, 145, -171, 206, -256, 317, -376, 463, -572, 694, -838, 1036, -1265, 1533, -1873, 2302, -2797, 3407 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,7
COMMENTS
Limiting ratio a(n+1)/a(n) is -1.2207440846057594..., which is a root of z^4 + z - 1.
LINKS
FORMULA
Recurrence a(i)= a(i-1) - a(i-3) + 2 a(i-4) - a(i-5).
a(n) = (-1)^n*A175790(n).
MAPLE
N:= 100: # to get terms up to index N
for i from 0 to 4 do a[i]:= coeftayl(1/(1+x^3-x^4)/(1-x), x=0, i) end do:
for i from 5 to N do a[i]:= a[i-1] - a[i-3] + 2*a[i-4] - a[i-5] end do:
[seq(a[i], i=0..N)]; # Robert Israel, Feb 11 2013
MATHEMATICA
CoefficientList[ Series[1/(1 - x + x^3 - 2 x^4 + x^5), {x, 0, 50}], x] (* Or *)
LinearRecurrence[{1, 0, -1, 2, -1}, {1, 1, 1, 0, 1}, 51] (* Robert G. Wilson v, Feb 11 2013 *)
CROSSREFS
Cf. A175790.
Sequence in context: A224928 A308066 A052173 * A175790 A124305 A349395
KEYWORD
sign,easy
AUTHOR
Roger L. Bagula, Dec 13 2010
EXTENSIONS
Recurrence, reference to A175790, and comment edited by Robert Israel, Feb 11 2013
STATUS
approved

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Last modified June 18 11:55 EDT 2024. Contains 373481 sequences. (Running on oeis4.)