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A102516
Sum C(n-3k,3k+1), k=0..floor(n/6).
1
0, 1, 2, 3, 4, 5, 6, 8, 13, 24, 45, 81, 138, 224, 352, 546, 851, 1348, 2175, 3556, 5843, 9582, 15624, 25317, 40836, 65737, 105863, 170796, 276160, 447272, 724968, 1174985, 1903186, 3080367, 4982688, 8057421, 13029534, 21074012, 34094041
OFFSET
0,3
FORMULA
G.f.: x(1-x)/((1-x)^3-x^6); a(n)=sum{k=0..floor(n/6), C(n-3k, 3k+1)}.
MATHEMATICA
LinearRecurrence[{3, -3, 1, 0, 0, 1}, {0, 1, 2, 3, 4, 5}, 40] (* Harvey P. Dale, Aug 06 2018 *)
CROSSREFS
Cf. A101551.
Sequence in context: A306075 A049432 A352821 * A156981 A271949 A039089
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Jan 13 2005
STATUS
approved