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Table of n, a(n) for n=1..65.
Index entries for linear recurrences with constant coefficients, signature (0, 2, 0, -1).
a(n)=(1/4)*(14*n+12*n*(-1)^n+1+(-1)^(n-1)) for n>1
Sequence in context: A008832 A180704 A040168 * A031066 A154355 A078421
Adjacent sequences: A176590 A176591 A176592 * A176594 A176595 A176596
Vincenzo Librandi, Apr 23 2010
Partially edited by N. J. A. Sloane, Jun 23 2010