OFFSET
0,3
LINKS
Michael De Vlieger, Table of n, a(n) for n = 0..1000
FORMULA
Conjecture: g.f.: -x*(-1+2*x) / ( (x-1)^2*(x^2-x+1)^2 ). - R. J. Mathar, Oct 09 2013
EXAMPLE
a(0,n): 0, 1, 0, -3, -4, ...
a(1,n): 0, 1, 1, -2, -6, ...
a(2,n): 0, 1, 2, 0, -6, ...
a(3,n): 0, 1, 3, 3, -3, ...
a(4,n): 0, 1, 4, 7, 4, ...
Main diagonal of array is 0, 1, 2, 3, 4, ...
MAPLE
A11066x := proc(mmax, nmax) local a, i, j ; a := array(0..mmax, 0..nmax) ; a[0, 0] := 0 ; for i from 1 to nmax do a[0, i] := i-sum(binomial(2*i-k-1, i-1)*a[0, k], k=0..i-1) : od ; for j from 1 to mmax do a[j, 0] := 0 ; for i from 1 to nmax do a[j, i] := a[j-1, i]+a[j, i-1] ; od ; od ; RETURN(a) ; end :
nmax := 100 : m := 2: a := A11066x(m, nmax) :
for n from 0 to nmax do printf("%d, ", a[m, n]) ; od ; # R. J. Mathar, Sep 01 2006
MATHEMATICA
a[m_, n_] := a[m, n] = Which[n == 0, 0, m == 0, n - Sum[ Binomial[2 n - k - 1, n - 1]*a[0, k], {k, 0, (n - 1)}], True, a[m - 1, n] + a[m, n - 1]]; Array[a[2, #] &, 76, 0] (* Michael De Vlieger, Sep 04 2017 *)
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Leroy Quet, Aug 02 2005
EXTENSIONS
More terms from R. J. Mathar, Sep 01 2006
STATUS
approved