A017860 Expansion of 1/(1-x^7-x^8-x^9-x^10-x^11).

1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 1, 2, 3, 4, 5, 4, 3, 3, 4, 6, 10, 15, 18, 19, 19, 19, 20, 26, 38, 53, 68, 81, 90, 95, 103, 122, 156, 205, 266, 330, 387, 437, 491, 566, 681, 852, 1079, 1344, 1625, 1911, 2211, 2562

Offset

0,16

Comments

Number of compositions of n into parts p where 7 <= p <= 11. [Joerg Arndt, Jun 28 2013]

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,1,1,1,1,1).

Formula

a(n) = 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[7, 11]]), {x, 0, 70}], x] (* Vincenzo Librandi, Jun 28 2013 *)
LinearRecurrence[{0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1}, {1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1}, 60] (* Harvey P. Dale, Jun 03 2023 *)

Prog

(Magma) m:=70; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/(1-x^7-x^8-x^9-x^10-x^11))); /* or */ I:=[1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1]; [n le 11 select I[n] else 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: A271800 A073792 A017870 * A328765 A368822 A270434

Adjacent sequences: A017857 A017858 A017859 * A017861 A017862 A017863

Keyword

nonn,easy

Author

N. J. A. Sloane.

Status

approved