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A077397
Expansion of (1+31*x-2*x^2-2*x^3)/(1-16*x^2+x^4).
2
1, 31, 14, 494, 223, 7873, 3554, 125474, 56641, 1999711, 902702, 31869902, 14386591, 507918721, 229282754, 8094829634, 3654137473, 129009355423, 58236916814, 2056054857134, 928136531551, 32767868358721, 14791947588002, 522229838882402, 235743024876481
OFFSET
0,2
FORMULA
a(2*n+4) = 16*a(2*n+2) - a(2*n), with a(0)=1, a(2)=14;
a(2*n+5) = 16*a(2*n+3) - a(2n+1), with a(1)=31, a(3)=494.
a(n) = 16*a(n-2) - a(n-4) for n>3. - Colin Barker, Jul 27 2020
MATHEMATICA
CoefficientList[Series[(1+31x-2x^2-2x^3)/(1-16x^2+x^4), {x, 0, 40}], x] (* Harvey P. Dale, Mar 25 2011 *)
PROG
(PARI) x='x+O('x^30); Vec((1+31*x-2*x^2-2*x^3)/(1-16*x^2+x^4)) \\ G. C. Greubel, Jan 18 2018
(Magma) Q:=Rationals(); R<x>:=PowerSeriesRing(Q, 30); Coefficients(R!(1+31*x-2*x^2-2*x^3)/(1-16*x^2+x^4))); // G. C. Greubel, Jan 18 2018
CROSSREFS
Used for calculating the values in A077398
Sequence in context: A040934 A320431 A107114 * A040933 A033351 A240910
KEYWORD
easy,nonn
AUTHOR
Bruce Corrigan (scentman(AT)myfamily.com), Nov 05 2002
EXTENSIONS
More terms from Harvey P. Dale, Mar 25 2011
STATUS
approved