OFFSET
1,1
LINKS
Index entries for linear recurrences with constant coefficients, signature (-7,-21,-35,-35,-21,-7,-1).
FORMULA
From Chai Wah Wu, Sep 24 2020: (Start)
a(n) = - 7*a(n-1) - 21*a(n-2) - 35*a(n-3) - 35*a(n-4) - 21*a(n-5) - 7*a(n-6) - a(n-7) for n > 7.
G.f.: x*(-24*x^6 - 162*x^5 - 467*x^4 - 744*x^3 - 786*x^2 - 30*x - 299)/(x + 1)^7. (End)
MAPLE
nmax:=27; mmax:=nmax: for m from 1 to mmax do BETA(2, m):=0 end do: BETA(2, 1):=-1: for n from 3 to nmax do BETA(n, 1):=(2*n-3)^2*BETA(n-1, 1)-(2*n-4)! end do: for n from 3 to nmax do for m from 2 to mmax do BETA(n, m):=(2*n-3)^2*BETA(n-1, m)-BETA(n-1, m-1) end do end do: for n from 4 to nmax do a(n-3):=BETA(n, n-3) od: seq(a(n), n=1..nmax-3);
MATHEMATICA
LinearRecurrence[{-7, -21, -35, -35, -21, -7, -1}, {-299, 2063, -8948, 29034, -77537, 180137, -376946}, 30] (* Harvey P. Dale, Jul 23 2021 *)
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Johannes W. Meijer, May 24 2009
STATUS
approved