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A017851
Expansion of 1/(1-x^6-x^7-x^8-x^9-x^10-x^11).
1
1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 6, 7, 9, 12, 16, 21, 26, 31, 37, 45, 56, 71, 91, 115, 143, 176, 216, 266, 331, 415, 521, 652, 812, 1007, 1247, 1547, 1925, 2401, 2997, 3738, 4654, 5786, 7190
OFFSET
0,14
COMMENTS
Number of compositions of n into parts p where 6 <= p <= 11. [Joerg Arndt, Jun 28 2013]
LINKS
FORMULA
a(n) = a(n-6) +a(n-7) +a(n-8) +a(n-9) +a(n-10) +a(n-11) for n>10. - Vincenzo Librandi, Jun 28 2013
MATHEMATICA
CoefficientList[Series[1 / (1 - Total[x^Range[6, 11]]), {x, 0, 60}], x] (* Vincenzo Librandi, Jun 28 2013 *)
PROG
(Magma) m:=70; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/(1-x^6-x^7-x^8-x^9-x^10-x^11))); /* or */ I:=[1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1]; [n le 11 select I[n] else Self(n-6)+Self(n-7)+Self(n-8)+Self(n-9)+Self(n-10)+Self(n-11): n in [1..70]]; // Vincenzo Librandi, Jun 28 2013
CROSSREFS
Sequence in context: A064524 A153249 A097621 * A345424 A359513 A358506
KEYWORD
nonn,easy
AUTHOR
STATUS
approved