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A147990
Array A147985 (Polynomial coefficients) with zeros deleted.
6
1, 1, -1, 1, -3, 1, 1, -7, 13, -7, 1, 1, -15, 83, -220, 303, -220, 83, -15, 1, 1, -31, 413, -3141, 15261, -50187, 115410, -189036, 222621, -189036, 115410, -50187, 15261, -3141, 413, -31, 1, 1, -63, 1839, -33150, 414861, -3841195, 27378213, -154299168
OFFSET
1,5
LINKS
FORMULA
Let s(1)=x and for n>=2, let s(n)=s(n,x)=S(n,y), where y=x^(1/2) and S(n,x)
is as at A147985. Then A147990 gives the coefficients of the polynomials s(n).
EXAMPLE
s(1)=x
s(2)=S(2,y)=x-1
s(3)=S(3,y)=x^2-3*x+1
s(4)=S(4,y)=x^4-7*x^3+13*x^2-7*x+1
so that as an array A147990 begins with
1
1 -1
1 -3 1
1 -7 13 -7 1
KEYWORD
sign,tabl
AUTHOR
Clark Kimberling, Nov 25 2008
STATUS
approved