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a(n)=(1/25)*{-188*(n mod 5)-23*[(n+1) mod 5]+47*[(n+2) mod 5]+117*[(n+3) mod 5]+282*[(n+4) mod 5]}-31*[C(2*n,n) mod 2], with n>=0 [From Paolo P. Lava, Jun 03 2009]