

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
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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(i1)  a(i3) + 2 a(i4)  a(i5).


MAPLE

N:= 100: # to get terms up to index N
for i from 0 to 4 do a[i]:= coeftayl(1/(1+x^3x^4)/(1x), x=0, i) end do:
for i from 5 to N do a[i]:= a[i1]  a[i3] + 2*a[i4]  a[i5] end do:


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



KEYWORD

sign,easy


AUTHOR



EXTENSIONS



STATUS

approved



