OFFSET
-2,5
COMMENTS
For n>=0, real parts of sum_(k=0)^n (k+i)^2, where i=sqrt(-1). [Bruno Berselli, Jan 24 2014]
LINKS
Michael De Vlieger, Table of n, a(n) for n = -2..10000
Francesco Toppan, Z_2 X Z_2-graded parastatistics in multiparticle quantum Hamiltonians, arXiv:2008.11554 [hep-th], 2020.
Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).
FORMULA
a(n) = 2*C(n+2,3) - C(n+2,2). - Zerinvary Lajos, Nov 25 2006
MAPLE
seq((2*n-3)*(n+2)*(n+1)/6, n=-2..40);
MATHEMATICA
s=0; lst={0, s}; Do[s+=n^2-1; AppendTo[lst, s], {n, 0, 6!, 1}]; lst (* Vladimir Joseph Stephan Orlovsky, Nov 07 2008 *)
Table[((2n-3)(n+2)(n+1))/6, {n, -2, 40}] (* Harvey P. Dale, Apr 21 2019 *)
CROSSREFS
KEYWORD
sign,easy
AUTHOR
N. J. A. Sloane, Dec 18 2000
STATUS
approved