OFFSET
0,1
FORMULA
a(n) = (1 - I/2)*(-1 - I)^n + (1 + I/2)*(-1 + I)^n, n>=0. - Taras Goy, Apr 20 2019
MAPLE
A134142 := proc(n) (-4)^floor(n/4)*op(1+(n mod 4), [2, -3, 2, 2]) ; end: for n from 0 to 80 do printf("%d ", A134142(n)) ; od: # R. J. Mathar, Feb 05 2008
CROSSREFS
KEYWORD
tabf,easy,sign
AUTHOR
Paul Curtz, Jan 29 2008
EXTENSIONS
More terms from R. J. Mathar, Feb 05 2008
STATUS
approved